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arch2
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2026-09-13 09:25:11 -04:00 · 2025-06-18 20:44:09 -04:00 · 2025-06-18 20:12:36 +02:00 · 2025-06-18 19:55:30 +02:00 · 2025-06-15 09:23:29 +01:00 · 2025-06-15 10:12:17 +02:00
62 changed files with 1198 additions and 1108 deletions
@@ -201,7 +201,7 @@ interfaces.
 The Strudel REPL is available at <https://strudel.cc>,
 including an interactive tutorial. The repository is at
-<https://github.com/tidalcycles/strudel>, all the code is open source
+<https://codeberg.org/uzu/strudel/releases>, all the code is open source
 under the GPL-3.0 License.
 # Acknowledgments
@@ -128,7 +128,7 @@ For the future, it is planned to integrate alternative sound engines such as Gli
 # Links
 The Strudel REPL is available at <https://strudel.cc>, including an interactive tutorial.
-The repository is at <https://github.com/tidalcycles/strudel>, all the code is open source under the GPL-3.0 License.
+The repository is at <https://codeberg.org/uzu/strudel/releases>, all the code is open source under the GPL-3.0 License.
 # Acknowledgments
@@ -0,0 +1,954 @@
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    <div id="header">
      <h1 class="title">Strudel: live coding patterns on the Web</h1>
      <ul id="authorlist">
        <li>true</li>
        <li>true</li>
      </ul>
      <h3 class="date">2022-12-14</h3>
    </div>
    <h2 class="abstract">Abstract</h2>
    <div id="abstract">
      <p>
        This paper introduces Strudel, which brings the TidalCycles approach to live coding algorithmic patterns to
        native JavaScript and the web. We begin by giving a little background of the first year of development, before
        sharing some detail about its implementation and examples of use. We go on to outline the wide range of
        synthesis and other outputs available in Strudel, including WebAudio, MIDI, OSC (for SuperDirt), WebSerial and
        CSound, and introduce Strudel’s REPL live editor, including its built-in visualisations. We then compare Strudel
        with Tidal, the trade-offs involved between JavaScript and Haskell, and the unique capabilities offered by
        Strudel for aligning patterns.
      </p>
    </div>
    <h1 data-number="1" id="introduction"><span class="header-section-number">1</span> Introduction</h1>
    <p>
      In the following paper, we introduce <em>Strudel</em>, an alternative implementation of the TidalCycles (or
      ‘Tidal’ for short) live coding system, using the JavaScript programming language. Strudel is an attempt to make
      live coding more accessible, by creating a system that runs entirely in the browser, while opening Tidal’s
      approach to algorithmic patterns
      <span class="citation" data-cites="mcleanAlgorithmicPattern2020a">(Mclean 2020)</span> up to modern audio/visual
      web technologies. The Strudel REPL is a live code editor dedicated to manipulating patterns while they play, with
      builtin visual feedback. While Strudel is written in JavaScript, the API is optimized for simplicity and
      readability by applying code transformations on the syntax tree level, allowing language operations that would
      otherwise be impossible. The application supports multiple ways to output sound, including Tone.js, Web Audio
      Nodes, OSC (Open Sound Control) messages, Web Serial, Web MIDI and Csound. The project is split into multiple
      packages, allowing granular reuse in other applications. Apart from TidalCycles, Strudel draws inspiration from
      many prior existing projects like TidalVortex
      <span class="citation" data-cites="mcleanTidalVortexZero2022">(McLean et al. 2022)</span>, Gibber
      <span class="citation" data-cites="robertsGibberLiveCoding2012">(Roberts and Kuchera-morin 2012)</span>, Estuary
      <span class="citation" data-cites="ogbornEstuaryBrowserbasedCollaborative2017">(Ogborn et al. 2017)</span>, Hydra
      <span class="citation" data-cites="jackHydra2022">(Jack [2022] 2022)</span>, Ocarina
      <span class="citation" data-cites="solomonPurescriptocarina2022">(Solomon [2021] 2022)</span> and Feedforward
      <span class="citation" data-cites="mcleanFeedforward2020">(McLean 2020)</span>. This paper expands the Strudel
      Demo paper for the Web Audio Conference 2022
      <span class="citation" data-cites="StrudelWAC2022">(Roos and McLean 2022)</span>.
    </p>
    <p>
      The first tentative commit to the Strudel project was on 22nd January 2022 by Alex McLean, with the core
      representation implemented over the following few days. Although this was his first attempt at a JavaScript-based
      application, by 27th January, Alex had managed to upload the initial version to the ‘npm’ javascript package
      database, sharing with the wider community for comment. By 4th February, Felix Roos had discovered Strudel and
      contributed a ‘REPL’ user interface to it, and then contributed a scheduler the next day, so that Strudel could
      already make sound. At this point, Alex and Felix shared ownership to the repository, and the project has since
      proved to be a productive confluence of Felix’s own work into music representation and visualisation, with Alex’s
      experience with making Tidal. Felix has since become the primary contributor to Strudel, with Alex continuing to
      jump between developing both Strudel and Tidal. Aspects of Strudel’s development have therefore fed back into
      TidalCycles, and both systems have maintained a shared conceptual underpinning. We plan to continue working
      towards feature parity between these systems, although within the syntactical trade-offs and library ecosystems of
      JavaScript and Haskell, some divergence is inevitable and healthy.
    </p>
    <p>
      Over the first year of its life, Strudel is now a fully-fledged live coding environment, porting Tidal’s core
      represention of patterns, pattern transformations, and mininotation for polymetric sequences, combined with a
      wealth of features for synthesising and visualising those patterns.
    </p>
    <h1 data-number="2" id="from-tidal-to-strudel-and-back">
      <span class="header-section-number">2</span> From Tidal to Strudel and back
    </h1>
    <p>
      As mentioned above, the original Tidal is implemented as a domain specific language (DSL) embedded in the Haskell
      pure functional programming language, and takes advantage of Haskell’s terse syntax and advanced, ‘strong’ type
      system. JavaScript on the other hand, is a multi-paradigm programming language, with a dynamic type system.
      Because Tidal leans heavily on many of Haskell’s more unique features, it was not always clear that it could
      meaningfully be ported to a multi-paradigm scripting language. However, this possibility was already demonstrated
      with an earlier port to Python [TidalVortex;
      <span class="citation" data-cites="mcleanTidalVortexZero2022">McLean et al. (2022)</span>], and we have now
      successfully implemented Tidal’s pure functional representation of patterns in Strudel, including partial
      application, currying, and the functor, applicative and monadic structures that underlie Tidal’s expressive
      pattern transformations. The result is a terse and highly composable system, where everything is either a pattern,
      or a function for combining and manipulating patterns, offering a rich creative ground for exploration.
    </p>
    <p>
      This development process has been far from a one-way port, however. The process of porting Tidal’s concepts has
      also opened up new possibilities, some just from revisiting every design decision, and some from the particular
      affordances and constraints offered by JavaScript. This has lead to new features (and indeed bugfixes) that have
      found their way back to Tidal where appropriate, and ongoing work that we will return to in the conclusion of this
      paper.
    </p>
    <h1 data-number="3" id="representing-patterns">
      <span class="header-section-number">3</span> Representing Patterns
    </h1>
    <p>
      Patterns are the essence of Tidal. Its patterns are abstract entities that represent flows of time as functions,
      adapting a technique called pure functional reactive programming. Taking a time span as its input, a Pattern can
      output a set of events that happen within that time span. It depends on the structure of the Pattern how the
      events are located in time. From now on, this process of generating events from a time span will be called
      <strong>querying</strong>. Example:
    </p>
    <div class="sourceCode" id="cb1">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="kw">const</span> pattern <span class="op">=</span> <span class="fu">sequence</span>(c3<span class="op">,</span> [e3<span class="op">,</span> g3])</span>
 <span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="kw">const</span> events <span class="op">=</span> pattern<span class="op">.</span><span class="fu">queryArc</span>(<span class="dv">0</span><span class="op">,</span> <span class="dv">1</span>)</span>
 <span id="cb1-3"><a href="#cb1-3" aria-hidden="true" tabindex="-1"></a><span class="bu">console</span><span class="op">.</span><span class="fu">log</span>(events<span class="op">.</span><span class="fu">map</span>(e <span class="kw">=&gt;</span> e<span class="op">.</span><span class="fu">show</span>()))</span></code></pre>
    </div>
    <p>
      In this example, we create a pattern using the <code>sequence</code> function and <strong>query</strong> it for
      the time span from <code>0</code> to <code>1</code>. Those numbers represent units of time called
      <strong>cycles</strong>. The length of one cycle depends on the tempo, which defaults to one cycle per second. The
      resulting events are:
    </p>
    <div class="sourceCode" id="cb2">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a>[{ <span class="dt">value</span><span class="op">:</span> <span class="st">&#39;c3&#39;</span><span class="op">,</span> <span class="dt">begin</span><span class="op">:</span> <span class="dv">0</span><span class="op">,</span> <span class="dt">end</span><span class="op">:</span> <span class="dv">1</span><span class="op">/</span><span class="dv">2</span> }<span class="op">,</span></span>
 <span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a>{ <span class="dt">value</span><span class="op">:</span> <span class="st">&#39;e3&#39;</span><span class="op">,</span> <span class="dt">begin</span><span class="op">:</span> <span class="dv">1</span><span class="op">/</span><span class="dv">2</span><span class="op">,</span> <span class="dt">end</span><span class="op">:</span> <span class="dv">3</span><span class="op">/</span><span class="dv">4</span> }<span class="op">,</span></span>
 <span id="cb2-3"><a href="#cb2-3" aria-hidden="true" tabindex="-1"></a>{ <span class="dt">value</span><span class="op">:</span> <span class="st">&#39;g3&#39;</span><span class="op">,</span> <span class="dt">begin</span><span class="op">:</span> <span class="dv">3</span><span class="op">/</span><span class="dv">4</span><span class="op">,</span> <span class="dt">end</span><span class="op">:</span> <span class="dv">1</span> }]</span></code></pre>
    </div>
    <p>
      Each event has a value, a begin time and an end time, where time is represented as a fraction. In the above case,
      the events are placed in sequential order, where c3 takes the first half, and e3 and g3 together take the second
      half. This temporal placement is the result of the <code>sequence</code> function, which divides its arguments
      equally over one cycle. If an argument is an array, the same rule applies to that part of the cycle. In the
      example, e3 and g3 are divided equally over the second half of the whole cycle.
    </p>
    <p>
      The above examples do not represent how Strudel is used in practice. In the live coding editor, the user only has
      to type in the pattern itself, the querying will be handled by the scheduler. The scheduler will repeatedly query
      the pattern for events, which are then scheduled as sound synthesis or other event triggers. Also, the above event
      data structure has been simplified for readability.
    </p>
    <figure>
      <img
        src="images/strudel-screenshot2.png"
        style="width: 60%"
        alt="Screenshot of the Strudel ‘REPL’ live coding editor, including piano-roll visualisation."
      />
      <figcaption aria-hidden="true">
        Screenshot of the Strudel ‘REPL’ live coding editor, including piano-roll visualisation.
      </figcaption>
    </figure>
    <h1 data-number="4" id="making-patterns"><span class="header-section-number">4</span> Making Patterns</h1>
    <p>
      In practice, the end-user live coder will not deal with constructing patterns directly, but will rather build
      patterns using Strudel’s extensive combinator library to create, combine and transform patterns.
    </p>
    <p>
      The live coder will rarely use the <code>sequence</code> function as seen above, as sequencing is implicit in many
      functions. For example in the following, the <code>note</code> function constructs a pattern of notes, sequencing
      its arguments in the same manner as the previous example.
    </p>
    <div class="sourceCode" id="cb3">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="fu">note</span>(c3<span class="op">,</span> [e3<span class="op">,</span> g3])</span></code></pre>
    </div>
    <p>
      Perhaps more often, they will use the mini-notation for even terser notation of rhythmic sequences: [^This last
      example is also valid Tidal code, albeit the parenthesis is not required in its Haskell syntax in this case. Tidal
      does not support passing sequences as lists directly to the <code>note</code> function, however.].
    </p>
    <div class="sourceCode" id="cb4">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb4-1"><a href="#cb4-1" aria-hidden="true" tabindex="-1"></a><span class="fu">note</span>(<span class="st">&quot;c3 [e3 g3]&quot;</span>)</span></code></pre>
    </div>
    <p>
      Such sequences are often treated only a starting point for manipulation, where they then undergo pattern
      transformations such as repetition, symmetry, interference/combination or randomisation, potentially at multiple
      timescales. Because Strudel patterns are represented as pure functions of time rather than as data structures,
      very long and complex generative results can be represented and manipulated without having to store the resulting
      sequences in memory.
    </p>
    <h1 data-number="5" id="pattern-example"><span class="header-section-number">5</span> Pattern Example</h1>
    <p>
      The following example showcases how patterns can be utilized to create musical complexity from simple parts, using
      repetition and interference:
    </p>
    <div class="sourceCode" id="cb5">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;&lt;0 2 [4 6](3,4,1) 3&gt;&quot;</span></span>
 <span id="cb5-2"><a href="#cb5-2" aria-hidden="true" tabindex="-1"></a><span class="op">.</span><span class="fu">off</span>(<span class="dv">1</span><span class="op">/</span><span class="dv">4</span><span class="op">,</span> <span class="fu">add</span>(<span class="dv">2</span>))</span>
 <span id="cb5-3"><a href="#cb5-3" aria-hidden="true" tabindex="-1"></a><span class="op">.</span><span class="fu">off</span>(<span class="dv">1</span><span class="op">/</span><span class="dv">2</span><span class="op">,</span> <span class="fu">add</span>(<span class="dv">6</span>))</span>
 <span id="cb5-4"><a href="#cb5-4" aria-hidden="true" tabindex="-1"></a><span class="op">.</span><span class="fu">scale</span>(<span class="st">&#39;D minor&#39;</span>)</span>
 <span id="cb5-5"><a href="#cb5-5" aria-hidden="true" tabindex="-1"></a><span class="op">.</span><span class="fu">legato</span>(<span class="op">.</span><span class="dv">25</span>)</span>
 <span id="cb5-6"><a href="#cb5-6" aria-hidden="true" tabindex="-1"></a><span class="op">.</span><span class="fu">note</span>()<span class="op">.</span><span class="fu">s</span>(<span class="st">&quot;sawtooth square&quot;</span>)</span>
 <span id="cb5-7"><a href="#cb5-7" aria-hidden="true" tabindex="-1"></a><span class="op">.</span><span class="fu">delay</span>(<span class="op">.</span><span class="dv">8</span>)<span class="op">.</span><span class="fu">delaytime</span>(<span class="op">.</span><span class="dv">125</span>)</span></code></pre>
    </div>
    <p>
      The pattern starts with a rhythm of numbers in mini notation, which are later interpreted inside the scale of D
      minor. The first line could also be expressed without mini notation:
    </p>
    <div class="sourceCode" id="cb6">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb6-1"><a href="#cb6-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cat</span>(<span class="dv">0</span><span class="op">,</span> <span class="dv">2</span><span class="op">,</span> [<span class="dv">4</span><span class="op">,</span> <span class="dv">6</span>]<span class="op">.</span><span class="fu">euclid</span>(<span class="dv">3</span><span class="op">,</span> <span class="dv">4</span><span class="op">,</span> <span class="dv">1</span>)<span class="op">,</span> <span class="dv">3</span>)</span></code></pre>
    </div>
    <p>
      These numbers then undergo various pattern transformations. Here is a short description of all the functions used:
    </p>
    <ul>
      <li><code>cat</code>: play elements sequentially, where each lasts one cycle</li>
      <li><code>brackets</code>: elements inside brackets are divided equally over the time of their parent</li>
      <li>
        <code>.euclid(p, s, o)</code>: place p pulses evenly over s steps, with offset o
        <span class="citation" data-cites="toussaintEuclideanAlgorithmGenerates2005">(Toussaint 2005)</span>
      </li>
      <li>
        <code>.off(n, f)</code>: layers a pattern on top of itself, with the new layer offset by n cycles, and with
        function f applied
      </li>
      <li><code>.legato(n)</code>: multiply the duration of all events in a pattern by a factor of n</li>
      <li>
        <code>.echo(t, n, v)</code>: copy each event t times, with n cycles in between each copy, decreasing velocity by
        v
      </li>
      <li><code>.note()</code>: interpretes values as notes</li>
      <li><code>.s(name)</code>: play back each event with the given sound</li>
      <li><code>.delay(wet)</code>: add delay</li>
      <li><code>.delaytime(t)</code>: set delay time</li>
    </ul>
    <p>Much of the above will be familiar to Tidal users.</p>
    <!-- This example shows some of Strudel's unique support for chords and transposition familiar to students of Western music theory. This differs a little from Tidal's approach and thanks to the integration of the javascript library XXX (*TODO* ? or is this all your work Felix?), Strudel's support for tonal transformations such as voice leading is perhaps respects more advanced than Tidal. -->
    <h1 data-number="6" id="ways-to-make-sound-and-other-events">
      <span class="header-section-number">6</span> Ways to make Sound (and other events)
    </h1>
    <p>To generate sound, Strudel supports bindings for different outputs:</p>
    <ul>
      <li>Tone.js (deprecated)</li>
      <li>Web Audio API</li>
      <li>WebDirt, a js recreation of Tidal’s <em>Dirt</em> sample engine (deprecated)</li>
      <li>OSC via osc-js, compatible with superdirt</li>
      <li>Csound via the Csound WebAssembly build</li>
      <li>MIDI via WebMIDI</li>
      <li>Serial via WebSerial</li>
    </ul>
    <p>
      At first, we used Tone.js as sound output, but it proved to be limited for the use case of Strudel, where each
      individual event could potentially have a completely different audio graph. While the Web Audio API takes a
      <em>fire-and-forget</em> approach, creating a lot of Tone.js instruments and effects causes performance issues
      quickly. For that reason, we chose to search for alternatives.
    </p>
    <p>
      Strudel’s new default output uses the Web Audio API to create a new audio graph for each event. It currently
      supports basic oscillators, sample playback, various effects and an experimental support for soundfonts.
    </p>
    <p>
      WebDirt <span class="citation" data-cites="ogbornDktr0WebDirt2022">(Ogborn [2016] 2022)</span> was created as part
      of the Estuary Live Coding System
      <span class="citation" data-cites="ogbornEstuaryBrowserbasedCollaborative2017">(Ogborn et al. 2017)</span>, and
      proved to be a solid choice for handling samples in Strudel as well. We are however focused on working more
      directly with the Web Audio API to be able to integrate new features more tightly.
    </p>
    <p>
      Using the OSC protocol via Strudel’s provided Node.js-based OSC proxy server, it is possible to send network
      messages to trigger events. This is mainly used to render sound using SuperDirt
      <span class="citation" data-cites="SuperDirt2022">(<em>SuperDirt</em> [2015] 2022)</span>, which is the
      well-developed Supercollider-based synthesis framework that Tidal live coders generally use as standard.
    </p>
    <p>
      Recently, the experimental integration of Csound proved to bring a new dimension of sound design capabilities to
      Strudel. Thanks to the WebAssembly distribution of this classic system
      <span class="citation" data-cites="CsoundWebAssembly">(Yi, Lazzarini, and Costello 2018)</span>, Csound
      ‘orchestra’ synthesisers can be embedded in and then patterned with Strudel code.
    </p>
    <p>
      MIDI output can also be used to send MIDI messages to either external instruments or to other programs on the same
      device. Unlike OSC, Strudel is able to send MIDI directly without requiring additional proxy software, but only
      from web browsers that support it (at the time of writing, this means Chromium-based browsers).
    </p>
    <p>
      Finally, Strudel supports Serial output, for example to trigger events via microcontrollers. This has already been
      explored for robot choreography by Kate Sicchio and Alex McLean, via a performance presented at the International
      Conference on Live Interfaces 2022.
    </p>
    <h1 data-number="7" id="the-strudel-repl"><span class="header-section-number">7</span> The Strudel REPL</h1>
    <p>
      While Strudel can be used as a library in any JavaScript codebase, its main, reference user interface is the
      Strudel REPL[^REPL stands for read, evaluate, print/play, loop. It is friendly jargon for an interactive
      programming interface from computing heritage, usually for a commandline interface but also applied to live coding
      editors.], which is a browser-based live coding environment. This live code editor is dedicated to manipulating
      Strudel patterns while they play. The REPL features built-in visual feedback, which highlights which elements in
      the patterned (mini-notation) sequences are influencing the event that is currently being played. This feedback is
      designed to support both learning and live use of Strudel.
    </p>
    <p>
      Besides a UI for playback control and meta information, the main part of the REPL interface is the code editor
      powered by CodeMirror. In it, the user can edit and evaluate pattern code live, using one of the available
      synthesis outputs to create music and/or sound art. The control flow of the REPL follows 3 basic steps:
    </p>
    <ol type="1">
      <li>
        The user writes and updates code. Each update transpiles and evaluates it to create a
        <code>Pattern</code> instance
      </li>
      <li>
        While the REPL is running, the <code>Scheduler</code> queries the active <code>Pattern</code> by a regular
        interval, generating <code>Events</code> (also known as <code>Haps</code> in Strudel) for the next time span.
      </li>
      <li>
        For each scheduling tick, all generated <code>Events</code> are triggered by calling their
        <code>onTrigger</code> method, which is set by the output.
      </li>
    </ol>
    <figure>
      <img
        src="https://github.com/tidalcycles/strudel/raw/talk/talk/public/strudelflow.png?raw=true"
        style="width: 43%"
        alt="REPL control flow"
      />
      <figcaption aria-hidden="true">REPL control flow</figcaption>
    </figure>
    <h2 data-number="7.1" id="user-code"><span class="header-section-number">7.1</span> User Code</h2>
    <p>To create a <code>Pattern</code> from the user code, two steps are needed:</p>
    <ol type="1">
      <li>Transpile the JS input code to make it functional</li>
      <li>Evaluate the transpiled code</li>
    </ol>
    <h3 data-number="7.1.1" id="transpilation-evaluation">
      <span class="header-section-number">7.1.1</span> Transpilation &amp; Evaluation
    </h3>
    <p>
      In the JavaScript world, using transpilation is a common practise to be able to use language features that are not
      supported by the base language. Tools like <code>babel</code> will transpile code that contains unsupported
      language features into a version of the code without those features.
    </p>
    <p>
      In the same tradition, Strudel can add a transpilation step to simplify the user code in the context of live
      coding. For example, the Strudel REPL lets the user create mini notation patterns using just double quoted
      strings, while single quoted strings remain what they are:
    </p>
    <div class="sourceCode" id="cb7">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;c3 [e3 g3]*2&quot;</span></span></code></pre>
    </div>
    <p>is transpiled to:</p>
    <div class="sourceCode" id="cb8">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb8-1"><a href="#cb8-1" aria-hidden="true" tabindex="-1"></a><span class="fu">mini</span>(<span class="st">&quot;c3 [e3 g3]*2&quot;</span>)<span class="op">.</span><span class="fu">withMiniLocation</span>([<span class="dv">1</span><span class="op">,</span><span class="dv">0</span><span class="op">,</span><span class="dv">0</span>]<span class="op">,</span>[<span class="dv">1</span><span class="op">,</span><span class="dv">14</span><span class="op">,</span><span class="dv">14</span>])</span></code></pre>
    </div>
    <p>
      Here, the string is wrapped in <code>mini</code>, which will create a pattern from a mini notation string.
      Additionally, the <code>withMiniLocation</code> method passes the original source code location of the string to
      the pattern, which enables highlighting active events.
    </p>
    <p>
      Other convenient features like pseudo variables, operator overloading and top level await are possible with
      transpilation.
    </p>
    <p>After the transpilation, the code is ready to be evaluated into a <code>Pattern</code>.</p>
    <p>
      Behind the scenes, the user code string is parsed with <code>acorn</code>, turning it into an Abstract Syntax Tree
      (AST). The AST allows changing the structure of the code before generating the transpiled version using
      <code>escodegen</code>.
    </p>
    <h3 data-number="7.1.2" id="mini-notation"><span class="header-section-number">7.1.2</span> Mini Notation</h3>
    <p>
      While the transpilation allows JavaScript to express Patterns in a less verbose way, it is still preferable to use
      the Mini Notation as a more compact way to express rhythm. Strudel aims to provide the same Mini Notation features
      and syntax as used in Tidal.
    </p>
    <p>
      The Mini Notation parser is implemented using <code>peggy</code>, which allows generating performant parsers for
      Domain Specific Languages (DSLs) using a concise grammar notation. The generated parser turns the Mini Notation
      string into an AST which is used to call the respective Strudel functions with the given structure. For example,
      <code>"c3 [e3 g3]*2"</code> will result in the following calls:
    </p>
    <div class="sourceCode" id="cb9">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="fu">seq</span>(</span>
 <span id="cb9-2"><a href="#cb9-2" aria-hidden="true" tabindex="-1"></a>  <span class="fu">reify</span>(<span class="st">&#39;c3&#39;</span>)<span class="op">.</span><span class="fu">withLocation</span>([<span class="dv">1</span><span class="op">,</span><span class="dv">1</span><span class="op">,</span><span class="dv">1</span>]<span class="op">,</span> [<span class="dv">1</span><span class="op">,</span><span class="dv">4</span><span class="op">,</span><span class="dv">4</span>])<span class="op">,</span></span>
 <span id="cb9-3"><a href="#cb9-3" aria-hidden="true" tabindex="-1"></a>  <span class="fu">seq</span>(</span>
 <span id="cb9-4"><a href="#cb9-4" aria-hidden="true" tabindex="-1"></a>    <span class="fu">reify</span>(<span class="st">&#39;e3&#39;</span>)<span class="op">.</span><span class="fu">withLocation</span>([<span class="dv">1</span><span class="op">,</span><span class="dv">5</span><span class="op">,</span><span class="dv">5</span>]<span class="op">,</span> [<span class="dv">1</span><span class="op">,</span><span class="dv">8</span><span class="op">,</span><span class="dv">8</span>])<span class="op">,</span></span>
 <span id="cb9-5"><a href="#cb9-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">reify</span>(<span class="st">&#39;g3&#39;</span>)<span class="op">.</span><span class="fu">withLocation</span>([<span class="dv">1</span><span class="op">,</span><span class="dv">8</span><span class="op">,</span><span class="dv">8</span>]<span class="op">,</span> [<span class="dv">1</span><span class="op">,</span><span class="dv">10</span><span class="op">,</span><span class="dv">10</span>])<span class="op">,</span></span>
 <span id="cb9-6"><a href="#cb9-6" aria-hidden="true" tabindex="-1"></a>  )<span class="op">.</span><span class="fu">fast</span>(<span class="dv">2</span>)</span>
 <span id="cb9-7"><a href="#cb9-7" aria-hidden="true" tabindex="-1"></a>)</span></code></pre>
    </div>
    <h3 data-number="7.1.3" id="highlighting-locations">
      <span class="header-section-number">7.1.3</span> Highlighting Locations
    </h3>
    <p>
      As seen in the examples above, both the JS and the Mini Notation parser add source code locations using
      <code>withMiniLocation</code> and <code>withLocation</code> methods. While the JS parser adds locations relative
      to the user code as a whole, the Mini Notation adds locations relative to the position of the mini notation
      string. The absolute location of elements within Mini Notation can be calculated by simply adding both locations
      together. This absolute location can be used to highlight active events in real time.
    </p>
    <h2 data-number="7.2" id="scheduling-events"><span class="header-section-number">7.2</span> Scheduling Events</h2>
    <p>
      After an instance of <code>Pattern</code> is obtained from the user code, it is used by the scheduler to get
      queried for events. Once started, the scheduler runs at a fixed interval to query active pattern for events
      withing the current interval’s time span. A simplified implementation looks like this:
    </p>
    <div class="sourceCode" id="cb10">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="kw">let</span> pattern <span class="op">=</span> <span class="fu">seq</span>(<span class="st">&#39;c3&#39;</span><span class="op">,</span> [<span class="st">&#39;e3&#39;</span><span class="op">,</span> <span class="st">&#39;g3&#39;</span>])<span class="op">;</span> <span class="co">// pattern from user</span></span>
 <span id="cb10-2"><a href="#cb10-2" aria-hidden="true" tabindex="-1"></a><span class="kw">let</span> interval <span class="op">=</span> <span class="fl">0.5</span><span class="op">;</span> <span class="co">// query interval in seconds</span></span>
 <span id="cb10-3"><a href="#cb10-3" aria-hidden="true" tabindex="-1"></a><span class="kw">let</span> time <span class="op">=</span> <span class="dv">0</span><span class="op">;</span> <span class="co">// beginning of current time span</span></span>
 <span id="cb10-4"><a href="#cb10-4" aria-hidden="true" tabindex="-1"></a><span class="kw">let</span> minLatency <span class="op">=</span> <span class="op">.</span><span class="dv">1</span><span class="op">;</span> <span class="co">// min time before a hap should trigger</span></span>
 <span id="cb10-5"><a href="#cb10-5" aria-hidden="true" tabindex="-1"></a><span class="pp">setInterval</span>(() <span class="kw">=&gt;</span> {</span>
 <span id="cb10-6"><a href="#cb10-6" aria-hidden="true" tabindex="-1"></a>  <span class="kw">const</span> haps <span class="op">=</span> pattern<span class="op">.</span><span class="fu">queryArc</span>(time<span class="op">,</span> time <span class="op">+</span> interval)<span class="op">;</span></span>
 <span id="cb10-7"><a href="#cb10-7" aria-hidden="true" tabindex="-1"></a>  time <span class="op">+=</span> interval<span class="op">;</span> <span class="co">// increment time</span></span>
 <span id="cb10-8"><a href="#cb10-8" aria-hidden="true" tabindex="-1"></a>  haps<span class="op">.</span><span class="fu">forEach</span>((hap) <span class="kw">=&gt;</span> {</span>
 <span id="cb10-9"><a href="#cb10-9" aria-hidden="true" tabindex="-1"></a>    <span class="kw">const</span> deadline <span class="op">=</span> hap<span class="op">.</span><span class="at">whole</span><span class="op">.</span><span class="at">begin</span> <span class="op">-</span> time <span class="op">+</span> minLatency<span class="op">;</span></span>
 <span id="cb10-10"><a href="#cb10-10" aria-hidden="true" tabindex="-1"></a>    <span class="fu">onTrigger</span>(hap<span class="op">,</span> deadline<span class="op">,</span> duration)<span class="op">;</span></span>
 <span id="cb10-11"><a href="#cb10-11" aria-hidden="true" tabindex="-1"></a>  })<span class="op">;</span></span>
 <span id="cb10-12"><a href="#cb10-12" aria-hidden="true" tabindex="-1"></a>}<span class="op">,</span> interval <span class="op">*</span> <span class="dv">1000</span>)<span class="op">;</span> <span class="co">// query each &quot;interval&quot; seconds</span></span></code></pre>
    </div>
    <p>
      Note that the above code is simplified for illustrative purposes. The actual implementation has to work around
      imprecise callbacks of <code>setInterval</code>. More about the implementation details can be read in
      <a href="https://loophole-letters.vercel.app/web-audio-scheduling">this blog post</a>.
    </p>
    <p>
      The fact that <code>Pattern.queryArc</code> is a pure function that maps a time span to a set of events allows us
      to choose any interval we like without changing the resulting output. It also means that when the pattern is
      changed from outside, the next scheduling callback will work with the new pattern, keeping its clock running.
    </p>
    <p>
      The latency between the time the pattern is evaluated and the change is heard is between
      <code>minLatency</code> and <code>interval + minLatency</code>, in our example between 100ms and 600ms. In
      Strudel, the current query interval is 50ms with a minLatency of 100ms, meaning the latency is between 50ms and
      150ms.
    </p>
    <h2 data-number="7.3" id="output"><span class="header-section-number">7.3</span> Output</h2>
    <p>
      The last step is to trigger each event in the chosen output. This is where the given time and value of each event
      is used to generate audio or any other form of time based output. The default output of the Strudel REPL is the
      WebAudio output. To understand what an output does, we first have to understand what control parameters are.
    </p>
    <h3 data-number="7.3.1" id="control-parameters">
      <span class="header-section-number">7.3.1</span> Control Parameters
    </h3>
    <p>
      To be able to manipulate multiple aspects of sound in parallel, so called control parameters are used to shape the
      value of each event. Example:
    </p>
    <div class="sourceCode" id="cb11">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="fu">note</span>(<span class="st">&quot;c3 e3&quot;</span>)<span class="op">.</span><span class="fu">cutoff</span>(<span class="dv">1000</span>)<span class="op">.</span><span class="fu">s</span>(<span class="st">&#39;sawtooth&#39;</span>)</span>
 <span id="cb11-2"><a href="#cb11-2" aria-hidden="true" tabindex="-1"></a>  <span class="op">.</span><span class="fu">queryArc</span>(<span class="dv">0</span><span class="op">,</span> <span class="dv">1</span>)<span class="op">.</span><span class="fu">map</span>(hap <span class="kw">=&gt;</span> hap<span class="op">.</span><span class="at">value</span>)</span>
 <span id="cb11-3"><a href="#cb11-3" aria-hidden="true" tabindex="-1"></a><span class="co">/* [</span></span>
 <span id="cb11-4"><a href="#cb11-4" aria-hidden="true" tabindex="-1"></a><span class="co">  { note: &#39;c3&#39;, cutoff: 1000, s: &#39;sawtooth&#39; }</span></span>
 <span id="cb11-5"><a href="#cb11-5" aria-hidden="true" tabindex="-1"></a><span class="co">  { note: &#39;e3&#39;, cutoff: 1000, s: &#39;sawtooth&#39; }</span></span>
 <span id="cb11-6"><a href="#cb11-6" aria-hidden="true" tabindex="-1"></a><span class="co">] */</span></span></code></pre>
    </div>
    <p>
      Here, the control parameter functions <code>note</code>, <code>cutoff</code> and <code>s</code> are used, where
      each controls a different property in the value object. Each control parameter function accepts a primitive value,
      a list of values to be sequenced into a <code>Pattern</code>, or a <code>Pattern</code>. In the example,
      <code>note</code> gets a <code>Pattern</code> from a Mini Notation expression (double quoted), while
      <code>cutoff</code> and <code>s</code> are given a <code>Number</code> and a (single quoted)
      <code>String</code> respectively.
    </p>
    <p>
      Strudel comes with a large default set of control parameter functions that are based on the ones used by Tidal and
      SuperDirt, focusing on music and audio terminology. It is however possible to create custom control paramters for
      any purpose:
    </p>
    <div class="sourceCode" id="cb12">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb12-1"><a href="#cb12-1" aria-hidden="true" tabindex="-1"></a><span class="kw">const</span> { x<span class="op">,</span> y } <span class="op">=</span> <span class="fu">createParams</span>(<span class="st">&#39;x&#39;</span><span class="op">,</span> <span class="st">&#39;y&#39;</span>)</span>
 <span id="cb12-2"><a href="#cb12-2" aria-hidden="true" tabindex="-1"></a><span class="fu">x</span>(sine<span class="op">.</span><span class="fu">range</span>(<span class="dv">0</span><span class="op">,</span> <span class="dv">200</span>))<span class="op">.</span><span class="fu">y</span>(cosine<span class="op">.</span><span class="fu">range</span>(<span class="dv">0</span><span class="op">,</span><span class="dv">200</span>))</span></code></pre>
    </div>
    <p>
      This example creates the custom control parameters <code>x</code> and <code>y</code> which are then used to form a
      pattern that descibes the coordinates of a circle.
    </p>
    <h3 data-number="7.3.2" id="outputs"><span class="header-section-number">7.3.2</span> Outputs</h3>
    <p>
      Now that we know how the value of an event is manipulated using control parameters, we can look at how outputs can
      use that value to generate anything. The scheduler above was calling the <code>onTrigger</code> function which is
      used to implement the output. A very simple version of the web audio output could look like this:
    </p>
    <div class="sourceCode" id="cb13">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="kw">function</span> <span class="fu">onTrigger</span>(hap<span class="op">,</span> deadline<span class="op">,</span> duration) {</span>
 <span id="cb13-2"><a href="#cb13-2" aria-hidden="true" tabindex="-1"></a>  <span class="kw">const</span> { note } <span class="op">=</span> hap<span class="op">.</span><span class="at">value</span><span class="op">;</span></span>
 <span id="cb13-3"><a href="#cb13-3" aria-hidden="true" tabindex="-1"></a>  <span class="kw">const</span> time <span class="op">=</span> <span class="fu">getAudioContext</span>()<span class="op">.</span><span class="at">currentTime</span> <span class="op">+</span> deadline<span class="op">;</span></span>
 <span id="cb13-4"><a href="#cb13-4" aria-hidden="true" tabindex="-1"></a>  <span class="kw">const</span> o <span class="op">=</span> <span class="fu">getAudioContext</span>()<span class="op">.</span><span class="fu">createOscillator</span>()<span class="op">;</span></span>
 <span id="cb13-5"><a href="#cb13-5" aria-hidden="true" tabindex="-1"></a>  o<span class="op">.</span><span class="at">frequency</span><span class="op">.</span><span class="at">value</span> <span class="op">=</span> <span class="fu">getFreq</span>(note)<span class="op">;</span></span>
 <span id="cb13-6"><a href="#cb13-6" aria-hidden="true" tabindex="-1"></a>  o<span class="op">.</span><span class="fu">start</span>(time)<span class="op">;</span></span>
 <span id="cb13-7"><a href="#cb13-7" aria-hidden="true" tabindex="-1"></a>  o<span class="op">.</span><span class="fu">stop</span>(time <span class="op">+</span> <span class="bu">event</span><span class="op">.</span><span class="at">duration</span>)<span class="op">;</span></span>
 <span id="cb13-8"><a href="#cb13-8" aria-hidden="true" tabindex="-1"></a>  o<span class="op">.</span><span class="fu">connect</span>(<span class="fu">getAudioContext</span>()<span class="op">.</span><span class="at">destination</span>)<span class="op">;</span></span>
 <span id="cb13-9"><a href="#cb13-9" aria-hidden="true" tabindex="-1"></a>}</span></code></pre>
    </div>
    <p>
      The above example will create an <code>OscillatorNode</code> for each event, where the frequency is controlled by
      the <code>note</code> param. In essence, this is how the WebAudio API output of Strudel works, only with many more
      parameters to control synths, samples and effects.
    </p>
    <h1 data-number="8" id="pattern-alignment-and-combination">
      <span class="header-section-number">8</span> Pattern alignment and combination
    </h1>
    <p>
      One core aspect of Strudel, inherited from Tidal, is the flexible way that patterns can be combined, irrespective
      of their structure. Its declarative approach means a live coder does not have to think about the details of
      <em>how</em> this is done, only <em>what</em> is to be done.
    </p>
    <p>
      As a simple example, consider two number patterns <code>"0 [1 2] 3"</code>, and <code>"10 20"</code>. The first
      has three contiguous steps of equal lengths, with the second step broken down into two substeps, giving four
      events in total. There are a very large number of ways in which the structure of these two patterns could be
      combined, but the default method in both Strudel and Tidal is to line up the cycles of the two patterns, and then
      take events from the first pattern and match them with those in the second pattern. Therefore, the following two
      lines are equivalent:
    </p>
    <div class="sourceCode" id="cb14">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb14-1"><a href="#cb14-1" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;0 [1 2] 3&quot;</span><span class="op">.</span><span class="fu">add</span>(<span class="st">&quot;10 20&quot;</span>)</span>
 <span id="cb14-2"><a href="#cb14-2" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;10 [11 22] 23&quot;</span></span></code></pre>
    </div>
    <p>
      Where the events only partially overlap, they are treated as fragments of the event in the first pattern. This is
      a little difficult to conceptualise, but lets start by comparing the two patterns in the following example:
    </p>
    <div class="sourceCode" id="cb15">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;0 1 2&quot;</span><span class="op">.</span><span class="fu">add</span>(<span class="st">&quot;10 20&quot;</span>)</span>
 <span id="cb15-2"><a href="#cb15-2" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;10 [11 21] 20&quot;</span></span></code></pre>
    </div>
    <p>
      They are similar to the previous example in that the number <code>1</code> is split in two, with its two halves
      added to <code>10</code> and <code>20</code> respectively. However, the <code>11</code> ‘remembers’ that it is a
      fragment of that original <code>1</code> event, and so is treated as having a duration of a third of a cycle,
      despite only being active for a sixth of a cycle. Likewise, the <code>21</code> is also a fragment of that
      original <code>1</code> event, but a fragment of its second half. Because the start of its event is missing, it
      wouldn’t actually trigger a sound (unless it underwent further pattern transformations/combinations).
    </p>
    <p>
      In practice, the effect of this default, implicit method for combining two patterns is that the second pattern is
      added <em>in</em> to the first one, and indeed this can be made explicit:
    </p>
    <div class="sourceCode" id="cb16">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;0 1 2&quot;</span><span class="op">.</span><span class="at">add</span><span class="op">.</span><span class="fu">in</span>(<span class="st">&quot;10 20&quot;</span>)</span></code></pre>
    </div>
    <p>This makes way for other ways to align the pattern, and several are already defined, in particular:</p>
    <ul>
      <li>
        <code>in</code> - as explained above, aligns cycles, and applies values from the pattern on the right
        <em>in</em> to the pattern on the left.
      </li>
      <li>
        <code>out</code> - as with <code>in</code>, but values are applied <em>out</em> of the pattern on the left
        (i.e. <em>in</em> to the one on the right).
      </li>
      <li>
        <code>mix</code> - structures from both patterns are combined, so that the new events are not fragments but are
        created at intersections of events from both sides.
      </li>
      <li>
        <code>squeeze</code> - cycles from the pattern on the right are squeezed into events on the left. So that
        e.g. <code>"0 1 2".add.squeeze("10 20")</code> is equivalent to <code>"[10 20] [11 21] [12 22]"</code>.
      </li>
      <li>
        <code>squeezeout</code> - as with <code>squeeze</code>, but cycles from the left are squeezed into events on the
        right. So, <code>"0 1 2".add.squeezeout("10 20")</code> is equivalent to <code>[10 11 12] [20 21 22]</code>.
      </li>
      <li>
        <code>trig</code> is similar to <code>squeezeout</code> in that cycles from the right are aligned with events on
        the left. However those cycles are not ‘squeezed’, rather they are truncated to fit the event. So
        <code>"0 1 2 3 4 5 6 7".add.trig("10 [20 30]")</code> would be equivalent to
        <code>10 11 12 13 20 21 30 31</code>. In effect, events on the right ‘trigger’ cycles on the left.
      </li>
      <li>
        <code>trigzero</code> is similar to <code>trig</code>, but the pattern is ‘triggered’ from its very first cycle,
        rather than from the current cycle. <code>trig</code> and <code>trigzero</code> therefore only give different
        results where the leftmost pattern differs from one cycle to the next.
      </li>
    </ul>
    <p>
      We will save going deeper into the background, design and practicalities of these alignment functions for future
      publications. However in the next section, we take them as a case study for looking at the different design
      affordances offered by Haskell to Tidal, and JavaScript to Strudel.
    </p>
    <h1 data-number="9" id="comparing-strudel-and-haskell-in-use">
      <span class="header-section-number">9</span> Comparing Strudel and Haskell in use
    </h1>
    <p>
      Unlike Haskell, JavaScript lacks the ability to define custom infix operators, or change the meaning of existing
      ones. So the above Strudel example of <code>"0 1 2".add.out("10 20")</code> is equivalent to the Tidal expression
      <code>"0 1 2" +| "10 20"</code>, where the vertical bar in the operator <code>+|</code> stands for
      <code>out</code> (where <code>a |+ b</code> would be equivalent of <code>a.add.in(b)</code>).
    </p>
    <p>
      From this we can already see that Tidal tends towards brevity through mixing infix operators with functions, and
      Strudel tends towards spelling out operations which are joined together with the <code>.</code> operator. This
      then is the design trade-off of Tidal’s tersity, versus Strudel’s simplicity.
    </p>
    <p>To demonstrate this, consider the following Tidal pattern:</p>
    <pre
      class="tidal"
    ><code>iter 4 $ every 3 (||+ n &quot;10 20&quot;) $ (n &quot;0 1 3&quot;) # s &quot;triangle&quot; # crush 4</code></pre>
    <p>This can be directly translated to the Strudel equivalent:</p>
    <div class="sourceCode" id="cb18">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="fu">iter</span>(<span class="dv">4</span><span class="op">,</span> <span class="fu">every</span>(<span class="dv">3</span><span class="op">,</span> add<span class="op">.</span><span class="fu">squeeze</span>(<span class="st">&quot;10 20&quot;</span>)<span class="op">,</span> <span class="fu">n</span>(<span class="st">&quot;0 1 3&quot;</span>)<span class="op">.</span><span class="fu">s</span>(<span class="st">&quot;triangle&quot;</span>)<span class="op">.</span><span class="fu">crush</span>(<span class="dv">4</span>)))</span></code></pre>
    </div>
    <p>Although for a more canonical Strudel expression, we would reorder it as:</p>
    <div class="sourceCode" id="cb19">
      <pre
        class="sourceCode js"
      ><code class="sourceCode javascript"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="fu">n</span>(<span class="st">&quot;0 1 3&quot;</span>)<span class="op">.</span><span class="fu">every</span>(<span class="dv">3</span><span class="op">,</span> add<span class="op">.</span><span class="fu">squeeze</span>(<span class="st">&quot;10 20&quot;</span>))<span class="op">.</span><span class="fu">iter</span>(<span class="dv">4</span>)<span class="op">.</span><span class="fu">s</span>(<span class="st">&quot;triangle&quot;</span>)<span class="op">.</span><span class="fu">crush</span>(<span class="dv">4</span>)</span></code></pre>
    </div>
    <p>
      The Strudel example uses the <code>.</code> method call operator for all operations and combinations, whereas the
      Tidal example has <code>#</code> for the default method for combining patterns and uses infix operators for other
      methods. The lack of parenthesis in the Tidal example is partly due to the way that arguments are applied to
      Haskell’s functions, and partly due to the use of the <code>$</code> operator as an alternative way to establish
      precedence and control the order of evaluation.
    </p>
    <p>
      Considering the above, we argue that the Haskell syntax is a little cleaner, but that the Strudel syntax is easier
      to learn. Our informal observation is that while Haskell’s dollar <code>$</code> operator is very useful in making
      code easier to work with, it is one of the most difficult aspects of Tidal use for beginners to learn. On the
      other hand, the deeper levels of parenthesis in Strudel code can be difficult to keep track of, especially while
      coding under pressure of live musical performance. However this difficulty can be largely be mitigated by
      reordering expressions, and further mitigated by supporting editor features.
    </p>
    <p>
      With Strudel, we have little choice but to embrace the affordances and constraints offered by JavaScript, and
      while designing a domain-specific language entirely based on method calls is a challenge, through creative
      adoption of functional programming techniques like partial application, we are so far very happy with the results.
      Tidal’s functional reactive approach to pattern-making has in general translated well to JavaScript, and
      opportunities and constraints have overall traded off to create a very approachable and useable live coding
      environment.
    </p>
    <h2 data-number="9.1" id="the-trade-off-of-flexible-typing">
      <span class="header-section-number">9.1</span> The trade-off of flexible typing
    </h2>
    <p>
      We have identified one problem with porting Tidal to JavaScript where we have missed Haskell’s strict typing and
      type inference. In both Tidal and Strudel, time is rational, where any point in time is represented as the ratio
      of two integers. This allows representation of musical ratios such that are impossible to represent accurately
      using the more common floating point numbers. However while libraries are available that support rational numbers
      in JavaScript, the lack of strict typing means that it is easy to implement pattern methods where computationally
      expensive conversion from floating point to rational numbers are performed late, and therefore often enough to
      overload the CPUs, due to the large number of iterative calculations required to estimate a ratio for a given
      floating point number. To mitigate this problem, we might consider moving to TypeScript in the future.
    </p>
    <h1 data-number="10" id="future-outlook"><span class="header-section-number">10</span> Future Outlook</h1>
    <p>
      The project is still young, with many features on the horizon. As general guiding principles, Strudel aims to be
    </p>
    <ol type="1">
      <li>accessible</li>
      <li>consistent with Tidal’s approach to pattern</li>
      <li>modular and extensible</li>
    </ol>
    <p>
      While Haskell’s type system makes it a great language for the ongoing development of Tidal’s inner representation
      of pattern, JavaScript’s vibrant ecosystem, flexibility and accessibility makes it a great host for more ad-hoc
      experiments, including interface design. For the future, it is planned to integrate additional alternative sound
      engines such as Glicol <span class="citation" data-cites="lanChaosprintGlicol2022">(Lan [2020] 2022)</span> and
      Faust
      <span class="citation" data-cites="FaustProgrammingLanguage2022"
        >(<em>Faust - Programming Language for Audio Applications and Plugins</em> [2016] 2022)</span
      >. Strudel is already approaching feature parity with Tidal, but there are more Tidal functions to be ported, and
      work to be done to improve compatibility with Tidal’s mininotation. Tidal version 2.0 is under development, which
      brings a new representation for sequences to its patterns, which will then be brought to Strudel. Besides sound,
      other ways to render events are being explored, such as graphical, and choreographic output. We are also looking
      into alternative ways of editing patterns, including multi-user editing for network music, parsing a novel syntax
      to escape the constraints of javascript, and developing hardware/e-textile interfaces. In summary, there is a lot
      of fun ahead.
    </p>
    <h1 data-number="11" id="links"><span class="header-section-number">11</span> Links</h1>
    <p>
      The Strudel REPL is available at <a href="https://strudel.cc" class="uri">https://strudel.cc</a>, including an
      interactive tutorial. The repository is at
      <a href="https://github.com/tidalcycles/strudel" class="uri">https://github.com/tidalcycles/strudel</a>, all the
      code is open source under the AGPL-3.0 License.
    </p>
    <h1 data-number="12" id="acknowledgments"><span class="header-section-number">12</span> Acknowledgments</h1>
    <p>
      Thanks to the Strudel and wider Tidal, live coding, WebAudio and free/open source software communities for
      inspiration and support. Alex McLean’s work on this project is supported by a UKRI Future Leaders Fellowship
      [grant number MR/V025260/1].
    </p>
    <h1 class="unnumbered" id="references">References</h1>
    <div id="refs" class="references csl-bib-body hanging-indent" role="doc-bibliography">
      <div id="ref-FaustProgrammingLanguage2022" class="csl-entry" role="doc-biblioentry">
        <em>Faust - Programming Language for Audio Applications and Plugins</em>. (2016) 2022. C++. GRAME.
        <a href="https://github.com/grame-cncm/faust">https://github.com/grame-cncm/faust</a>.
      </div>
      <div id="ref-jackHydra2022" class="csl-entry" role="doc-biblioentry">
        Jack, Olivia. (2022) 2022. <em>Hydra</em>.
        <a href="https://github.com/ojack/hydra">https://github.com/ojack/hydra</a>.
      </div>
      <div id="ref-lanChaosprintGlicol2022" class="csl-entry" role="doc-biblioentry">
        Lan, Qichao. (2020) 2022. <em>Chaosprint/Glicol</em>. Rust.
        <a href="https://github.com/chaosprint/glicol">https://github.com/chaosprint/glicol</a>.
      </div>
      <div id="ref-mcleanAlgorithmicPattern2020a" class="csl-entry" role="doc-biblioentry">
        Mclean, Alex. 2020. <span>“Algorithmic Pattern.”</span> In
        <em>Proceedings of the International Conference on New Interfaces for Musical Expression</em>, 265--270.
        Birmingham, UK. <a href="https://zenodo.org/record/4813352">https://zenodo.org/record/4813352</a>.
      </div>
      <div id="ref-mcleanFeedforward2020" class="csl-entry" role="doc-biblioentry">
        McLean, Alex. 2020. <span>“Feedforward.”</span> In
        <em>Proceedings of New Interfaces for Musical Expression</em>. Birmingham.
        <a href="https://zenodo.org/record/6353969">https://zenodo.org/record/6353969</a>.
      </div>
      <div id="ref-mcleanTidalVortexZero2022" class="csl-entry" role="doc-biblioentry">
        McLean, Alex, Raphaël Forment, Sylvain Le Beux, and Damián Silvani. 2022. <span>“TidalVortex Zero.”</span> In
        <em>Proceedings of the 7th International Conference on Live Coding</em>. Limerick, Ireland: Zenodo.
        <a href="https://doi.org/10.5281/zenodo.6456380">https://doi.org/10.5281/zenodo.6456380</a>.
      </div>
      <div id="ref-ogbornDktr0WebDirt2022" class="csl-entry" role="doc-biblioentry">
        Ogborn, David. (2016) 2022. <em>Dktr0/WebDirt</em>. JavaScript.
        <a href="https://github.com/dktr0/WebDirt">https://github.com/dktr0/WebDirt</a>.
      </div>
      <div id="ref-ogbornEstuaryBrowserbasedCollaborative2017" class="csl-entry" role="doc-biblioentry">
        Ogborn, David, Jamie Beverley, Luis Navarro del Angel, Eldad Tsabary, and Alex McLean. 2017.
        <span>“Estuary: Browser-Based Collaborative Projectional Live Coding of Musical Patterns.”</span> In
        <em>Proceedings of the International Conference on Live Coding</em>, 11. Morelia.
      </div>
      <div id="ref-robertsGibberLiveCoding2012" class="csl-entry" role="doc-biblioentry">
        Roberts, Charles, and Joann Kuchera-morin. 2012. <span>“Gibber: Live Coding Audio in the Browser.”</span> In
        <em>In Proceedings of the 2012 International Computer Music Conference</em>.
      </div>
      <div id="ref-StrudelWAC2022" class="csl-entry" role="doc-biblioentry">
        Roos, Felix, and Alex McLean. 2022. <span>“Strudel: Algorithmic Patterns for the Web.”</span> In. Zenodo.
        <a href="https://doi.org/10.5281/zenodo.6768844">https://doi.org/10.5281/zenodo.6768844</a>.
      </div>
      <div id="ref-solomonPurescriptocarina2022" class="csl-entry" role="doc-biblioentry">
        Solomon, Mike. (2021) 2022. <em>Purescript-Ocarina</em>. PureScript.
        <a href="https://github.com/mikesol/purescript-ocarina">https://github.com/mikesol/purescript-ocarina</a>.
      </div>
      <div id="ref-SuperDirt2022" class="csl-entry" role="doc-biblioentry">
        <em>SuperDirt</em>. (2015) 2022. SuperCollider. musikinformatik.
        <a href="https://github.com/musikinformatik/SuperDirt">https://github.com/musikinformatik/SuperDirt</a>.
      </div>
      <div id="ref-toussaintEuclideanAlgorithmGenerates2005" class="csl-entry" role="doc-biblioentry">
        Toussaint, Godfried. 2005. <span>“The Euclidean Algorithm Generates Traditional Musical Rhythms.”</span> In
        <em>In Proceedings of BRIDGES: Mathematical Connections in Art, Music and Science</em>, 47–56.
        <a href="http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.62.231"
          >http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.62.231</a
        >.
      </div>
      <div id="ref-CsoundWebAssembly" class="csl-entry" role="doc-biblioentry">
        Yi, Steven, Victor Lazzarini, and Edward Costello. 2018.
        <span>“WebAssembly AudioWorklet Csound.”</span> In. Berlin, Germany.
        <a href="https://mural.maynoothuniversity.ie/16018/">https://mural.maynoothuniversity.ie/16018/</a>.
      </div>
    </div>
  </body>
 </html>
@@ -451,7 +451,7 @@ While Haskell's type system makes it a great language for the ongoing developmen
 # Links
 The Strudel REPL is available at <https://strudel.cc>, including an interactive tutorial.
-The repository is at <https://github.com/tidalcycles/strudel>, all the code is open source under the AGPL-3.0 License.
+The repository is at <https://codeberg.org/uzu/strudel>, all the code is open source under the AGPL-3.0 License.
 # Acknowledgments
@@ -0,0 +1,63 @@
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@@ -1,4 +1,8 @@
-This document introduces you to Strudel in a technical sense. If you just want to *use* Strudel, have a look at the [Tutorial](https://strudel.tidalcycles.org/tutorial/).
+This document introduces you to Strudel in a technical sense. 
 It is rather out of date, but there might still be useful info below.
 If you just want to *use* Strudel, have a look at the [Tutorial](https://strudel.tidalcycles.org/tutorial/).
 ## Strudel Packages
@@ -17,11 +21,11 @@ More info in the [REPL README](https://codeberg.org/uzu/strudel/src/branch/main/
 # High Level Overview
-<img src="https://github.com/tidalcycles/strudel/blob/talk/talk/public/strudelflow.png?raw=true" width="600" />
+<img src="strudelflow.png" width="600" />
 ## 1. End User Code
-The End User Code is written in JavaScript with added syntax sugar. The [eval package](https://codeberg.org/uzu/strudel/src/branch/main/packages/eval#strudelcycleseval) evaluates the user code
+The End User Code is written in JavaScript with added syntax sugar. The [eval package](https://github.com/tidalcycles/strudel/tree/main/packages/eval#strudelcycleseval) evaluates the user code
 after a transpilation step, which resolves the syntax sugar. If you don't want the syntax sugar, you can omit the eval package and call the native javascript `eval` instead.
 ### 🍭 Syntax Sugar
@@ -54,13 +58,13 @@ This is how it works:
 - The AST is transformed to resolve the syntax sugar
 - The AST is used to generate code again (shift-codegen)
-Shift will most likely be replaced with acorn in the future, see https://codeberg.org/uzu/strudel/issues/174
+Shift will most likely be replaced with acorn in the future, see https://github.com/tidalcycles/strudel/issues/174
 ### Mini Notation
 Another important part of the user code is the mini notation, which allows to express rhythms in a short manner.
- the mini notation is [implemented as a PEG grammar](https://codeberg.org/uzu/strudel/src/branch/main/packages/mini/krill.pegjs), living in the [mini package](https://codeberg.org/uzu/strudel/src/branch/main/packages/mini)
+- the mini notation is [implemented as a PEG grammar](https://github.com/tidalcycles/strudel/blob/main/packages/mini/krill.pegjs), living in the [mini package](https://github.com/tidalcycles/strudel/tree/main/packages/mini)
 - it is based on [krill](https://github.com/Mdashdotdashn/krill) by Mdashdotdashn
 - the peg grammar is used to generate a parser with [peggyjs](https://peggyjs.org/)
 - the generated parser takes a mini notation string and outputs an AST
@@ -171,7 +175,7 @@ Here is an example Hap value with different properties:
 ```js
 { note: 'a4', s: 'sawtooth', gain: 0.5, cutoff: 267 }
 ```
-<img src="https://github.com/tidalcycles/strudel/blob/talk/talk/public/waa-nodes.png?raw=true" width="600" />
+<img src="waa-nodes.png" width="600" />
 <div className="text-left">
@@ -182,12 +186,12 @@ Here is an example Hap value with different properties:
 At the time of writing this doc, the following outputs are supported:
- Web Audio API `.out()` see [/webaudio](https://codeberg.org/uzu/strudel/src/branch/main/packages/webaudio)
+- Web Audio API `.out()` see [/webaudio](https://github.com/tidalcycles/strudel/tree/main/packages/webaudio)
- MIDI `.midi()` see [/midi](https://codeberg.org/uzu/strudel/src/branch/main/packages/midi)
+- MIDI `.midi()` see [/midi](https://github.com/tidalcycles/strudel/tree/main/packages/midi)
- OSC `.osc()` see [/osc](https://codeberg.org/uzu/strudel/src/branch/main/packages/osc)
+- OSC `.osc()` see [/osc](https://github.com/tidalcycles/strudel/tree/main/packages/osc)
- Serial `.serial()` see [/serial](https://codeberg.org/uzu/strudel/src/branch/main/packages/serial)
+- Serial `.serial()` see [/serial](https://github.com/tidalcycles/strudel/tree/main/packages/serial)
- Tone.js `.tone()` (deprecated?) [/tone](https://codeberg.org/uzu/strudel/src/branch/main/packages/tone)
+- Tone.js `.tone()` (deprecated?) [/tone](https://github.com/tidalcycles/strudel/tree/main/packages/tone)
- WebDirt `.webdirt()` (deprecated?) [/webdirt](https://codeberg.org/uzu/strudel/src/branch/main/packages/webdirt)
+- WebDirt `.webdirt()` (deprecated?) [/webdirt](https://github.com/tidalcycles/strudel/tree/main/packages/webdirt)
- Speech `.speak()` (experimental) part of [/core](https://codeberg.org/uzu/strudel/src/branch/main/packages/core)
+- Speech `.speak()` (experimental) part of [/core](https://github.com/tidalcycles/strudel/tree/main/packages/core)
-These could change, so make sure to check the [packages folder](https://codeberg.org/uzu/strudel/src/branch/main/packages).
+These could change, so make sure to check the [packages folder](https://github.com/tidalcycles/strudel/tree/main/packages).
@@ -2,4 +2,4 @@
 Each folder represents one of the @strudel/* packages [published to npm](https://www.npmjs.com/org/strudel).
-To understand how those pieces connect, refer to the [Technical Manual](https://codeberg.org/uzu/strudel/src/branch/main/technical-manual.md) or the individual READMEs.
+To understand how those pieces connect, refer to the [Technical Manual](https://codeberg.org/uzu/strudel/wiki/Technical-Manual) or the individual READMEs.
@@ -8,6 +8,11 @@ import CutiePi, { settings as CutiePiSettings } from './themes/CutiePi.mjs';
 import sonicPink, { settings as sonicPinkSettings } from './themes/sonic-pink.mjs';
 import redText, { settings as redTextSettings } from './themes/red-text.mjs';
 import greenText, { settings as greenTextSettings } from './themes/green-text.mjs';
 import archBtw, { settings as archBtwSettings } from './themes/archBtw.mjs';
 import fruitDaw, { settings as fruitDawSettings } from './themes/fruitDaw.mjs';
 import bluescreenlight, { settings as bluescreenlightsettings } from './themes/bluescreenlight.mjs';
 import androidstudio, { settings as androidstudioSettings } from './themes/androidstudio.mjs';
 import atomone, { settings as atomOneSettings } from './themes/atomone.mjs';
 import aura, { settings as auraSettings } from './themes/aura.mjs';
@@ -39,17 +44,20 @@ import { setTheme } from '@strudel/draw';
 export const themes = {
  strudelTheme,
  algoboy,
  archBtw,
  androidstudio,
  atomone,
  aura,
  bbedit,
  blackscreen,
  bluescreen,
  bluescreenlight,
  CutiePi,
  darcula,
  dracula,
  duotoneDark,
  eclipse,
  fruitDaw,
  githubDark,
  githubLight,
  greenText,
@@ -78,10 +86,12 @@ export const themes = {
 export const settings = {
  strudelTheme: strudelThemeSettings,
  bluescreen: bluescreenSettings,
  bluescreenlight: bluescreenlightsettings,
  blackscreen: blackscreenSettings,
  whitescreen: whitescreenSettings,
  teletext: teletextSettings,
  algoboy: algoboySettings,
  archBtw: archBtwSettings,
  androidstudio: androidstudioSettings,
  atomone: atomOneSettings,
  aura: auraSettings,
@@ -92,9 +102,11 @@ export const settings = {
  eclipse: eclipseSettings,
  CutiePi: CutiePiSettings,
  sonicPink: sonicPinkSettings,
  fruitDaw: fruitDawSettings,
  githubLight: githubLightSettings,
  githubDark: githubDarkSettings,
  greenText: greenTextSettings,
  gruvboxDark: gruvboxDarkSettings,
  gruvboxLight: gruvboxLightSettings,
  materialDark: materialDarkSettings,
@@ -0,0 +1,38 @@
 /*
 * Arch Btw
 * Modern terminal inspired theme
 * made by Jade
 */
 import { tags as t } from '@lezer/highlight';
 import { createTheme } from './theme-helper.mjs';
 const hex = ['rgb(0, 0, 0)', 'rgb(82, 208, 250)', 'rgba(113, 208, 250, .4)', 'rgba(113, 208, 250, .15)'];
 export const settings = {
  background: hex[0],
  lineBackground: 'transparent',
  foreground: hex[1],
  selection: hex[2],
  selectionMatch: hex[0],
  gutterBackground: hex[0],
  gutterForeground: hex[2],
  gutterBorder: 'transparent',
  lineHighlight: hex[0],
 };
 export default createTheme({
  theme: 'dark',
  settings,
  styles: [
    {
      tag: [t.function(t.variableName), t.function(t.propertyName), t.url, t.processingInstruction],
      color: hex[1],
    },
    { tag: [t.atom, t.bool, t.special(t.variableName)], color: hex[1] },
    { tag: [t.comment, t.brace, t.bracket], color: hex[2] },
    { tag: [t.variableName, t.propertyName, t.labelName], color: hex[1] },
    { tag: [t.attributeName, t.number], color: hex[1] },
    { tag: t.keyword, color: hex[1] },
    { tag: [t.string, t.regexp, t.special(t.propertyName)], color: hex[1] },
  ],
 });
@@ -0,0 +1,37 @@
 /*
 * A lighter blue screen theme
 * made by Jade
 */
 import { tags as t } from '@lezer/highlight';
 import { createTheme } from './theme-helper.mjs';
 const hex = ['rgb(75, 130, 247)', 'rgb(47, 108, 246)', 'rgb(255, 255, 255)', 'rgba(255, 255, 255,.3)'];
 export const settings = {
  background: hex[0],
  lineBackground: 'transparent',
  foreground: hex[2],
  selection: hex[3],
  selectionMatch: hex[0],
  gutterBackground: hex[0],
  gutterForeground: hex[2],
  gutterBorder: 'transparent',
  lineHighlight: hex[1],
 };
 export default createTheme({
  theme: 'dark',
  settings,
  styles: [
    {
      tag: [t.function(t.variableName), t.function(t.propertyName), t.url, t.processingInstruction],
      color: hex[2],
    },
    { tag: [t.atom, t.bool, t.special(t.variableName)], color: hex[2] },
    { tag: [t.comment, t.bracket, t.brace, t.compareOperator], color: hex[3] },
    { tag: [t.variableName, t.propertyName, t.labelName], color: hex[2] },
    { tag: [t.attributeName, t.number], color: hex[2] },
    { tag: t.keyword, color: hex[2] },
    { tag: [t.string, t.regexp, t.special(t.propertyName)], color: hex[2] },
  ],
 });
@@ -0,0 +1,50 @@
 /*
 * Fruit Daw
 * made by Jade
 */
 import { tags as t } from '@lezer/highlight';
 import { createTheme } from './theme-helper.mjs';
 const hex = [
  'rgb(84, 93, 98)',
  'rgb(255, 255, 255)',
  'rgba(255, 255, 255, .25)',
  'rgb(67, 76, 81)',
  'rgb(186, 230, 115)',
  'rgb(252, 184, 67)',
  'rgb(124, 206, 254)',
  'rgb(83, 101, 102)',
  'rgba(46, 62, 72,.5)',
  'rgb(94, 100, 108)',
  'rgb(167, 216, 177)',
 ];
 export const settings = {
  background: hex[0],
  lineBackground: 'transparent',
  foreground: hex[10],
  selection: hex[8],
  selectionMatch: hex[0],
  gutterBackground: hex[3],
  gutterForeground: hex[2],
  gutterBorder: 'transparent',
  lineHighlight: hex[3],
 };
 export default createTheme({
  theme: 'dark',
  settings,
  styles: [
    {
      tag: [t.function(t.variableName), t.function(t.propertyName), t.url, t.processingInstruction],
      color: hex[1],
    },
    { tag: [t.bool, t.special(t.variableName)], color: hex[1] },
    { tag: [t.comment, t.brace, t.bracket], color: hex[2] },
    { tag: [t.variableName], color: hex[1] },
    { tag: [t.labelName, t.propertyName, t.self, t.atom], color: hex[5] },
    { tag: [t.attributeName, t.number], color: hex[6] },
    { tag: t.keyword, color: hex[5] },
    { tag: [t.string, t.regexp, t.special(t.propertyName)], color: hex[4] },
  ],
 });
@@ -1,6 +1,6 @@
 /*
 controls.test.mjs - <short description TODO>
-Copyright (C) 2023 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/packages/core/test/controls.test.mjs>
+Copyright (C) 2023 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/packages/core/test/controls.test.mjs>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
@@ -1,6 +1,6 @@
 /*
 drawLine.test.mjs - <short description TODO>
-Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/packages/core/test/drawLine.test.mjs>
+Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/packages/core/test/drawLine.test.mjs>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
@@ -1,6 +1,6 @@
 /*
 fraction.test.mjs - <short description TODO>
-Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/packages/core/test/fraction.test.mjs>
+Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/packages/core/test/fraction.test.mjs>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
@@ -1,6 +1,6 @@
 /*
 pattern.test.mjs - <short description TODO>
-Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/packages/core/test/pattern.test.mjs>
+Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/packages/core/test/pattern.test.mjs>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
@@ -884,7 +884,7 @@ describe('Pattern', () => {
      );
    });
    it('Doesnt drop haps in the 9th cycle', () => {
-      // fixed with https://github.com/tidalcycles/strudel/commit/72eeaf446e3d5e186d63cc0d2276f0723cde017a
+      // fixed with https://codeberg.org/uzu/strudel/commit/72eeaf446e3d5e186d63cc0d2276f0723cde017a
      expect(sequence(1, 2, 3).ply(2).early(8).firstCycle().length).toBe(6);
    });
  });
@@ -1,6 +1,6 @@
 /*
 util.test.mjs - Tests for the core 'util' module
-Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/packages/core/test/util.test.mjs>
+Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/packages/core/test/util.test.mjs>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
@@ -1,6 +1,6 @@
 /*
 mini.test.mjs - <short description TODO>
-Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/packages/mini/test/mini.test.mjs>
+Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/packages/mini/test/mini.test.mjs>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
@@ -17,7 +17,7 @@ You can also pin the version like this:
 ```
 This has the advantage that your code will always work, regardless of potential breaking changes in the strudel codebase.
-See [releases](https://github.com/tidalcycles/strudel/releases) for the latest versions.
+See [releases](https://codeberg.org/uzu/strudel/releases) for the latest versions.
 ## Use Web Component
@@ -91,7 +91,7 @@ or
 </script>
 ```
-The `.editor` property on the `strudel-editor` web component gives you the instance of [StrudelMirror](https://github.com/tidalcycles/strudel/blob/a46bd9b36ea7d31c9f1d3fca484297c7da86893f/packages/codemirror/codemirror.mjs#L124) that runs the REPL.
+The `.editor` property on the `strudel-editor` web component gives you the instance of [StrudelMirror](https://codeberg.org/uzu/strudel/src/branch/a46bd9b36ea7d31c9f1d3fca484297c7da86893f/packages/codemirror/codemirror.mjs#L124) that runs the REPL.
 For example, you could use `setCode` to change the code from the outside, `start` / `stop` to toggle playback or `evaluate` to evaluate the code.
@@ -1,6 +1,6 @@
 /*
 tonal.test.mjs - <short description TODO>
-Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/packages/tonal/test/tonal.test.mjs>
+Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/packages/tonal/test/tonal.test.mjs>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
@@ -1,6 +1,6 @@
 /*
 tonleiter.test.mjs - <short description TODO>
-Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/packages/tonal/test/tonleiter.test.mjs>
+Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/packages/tonal/test/tonleiter.test.mjs>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
@@ -1,6 +1,6 @@
 /*
 transpiler.test.mjs - <short description TODO>
-Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/packages/transpiler/test/transpiler.test.mjs>
+Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/packages/transpiler/test/transpiler.test.mjs>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
@@ -1,6 +1,6 @@
 /*
 xen.test.mjs - <short description TODO>
-Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/packages/xen/test/xen.test.mjs>
+Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/packages/xen/test/xen.test.mjs>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
@@ -1,818 +0,0 @@
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  <title>Strudel: live coding patterns on the Web</title>
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 <body>
 <div id="header">
 <h1 class="title">Strudel: live coding patterns on the Web</h1>
 <ul id="authorlist">
 <li>true</li>
 <li>true</li>
 </ul>
 <h3 class="date">2022-12-14</h3>
 </div>
 <h2 class="abstract">Abstract</h2>
 <div id="abstract">
 <p>This paper introduces Strudel, which brings the TidalCycles approach
 to live coding algorithmic patterns to native JavaScript and the web. We
 begin by giving a little background of the first year of development,
 before sharing some detail about its implementation and examples of use.
 We go on to outline the wide range of synthesis and other outputs
 available in Strudel, including WebAudio, MIDI, OSC (for SuperDirt),
 WebSerial and CSound, and introduce Strudel’s REPL live editor,
 including its built-in visualisations. We then compare Strudel with
 Tidal, the trade-offs involved between JavaScript and Haskell, and the
 unique capabilities offered by Strudel for aligning patterns.</p>
 </div>
 <h1 data-number="1" id="introduction"><span
 class="header-section-number">1</span> Introduction</h1>
 <p>In the following paper, we introduce <em>Strudel</em>, an alternative
 implementation of the TidalCycles (or ‘Tidal’ for short) live coding
 system, using the JavaScript programming language. Strudel is an attempt
 to make live coding more accessible, by creating a system that runs
 entirely in the browser, while opening Tidal’s approach to algorithmic
 patterns <span class="citation"
 data-cites="mcleanAlgorithmicPattern2020a">(Mclean 2020)</span> up to
 modern audio/visual web technologies. The Strudel REPL is a live code
 editor dedicated to manipulating patterns while they play, with builtin
 visual feedback. While Strudel is written in JavaScript, the API is
 optimized for simplicity and readability by applying code
 transformations on the syntax tree level, allowing language operations
 that would otherwise be impossible. The application supports multiple
 ways to output sound, including Tone.js, Web Audio Nodes, OSC (Open
 Sound Control) messages, Web Serial, Web MIDI and Csound. The project is
 split into multiple packages, allowing granular reuse in other
 applications. Apart from TidalCycles, Strudel draws inspiration from
 many prior existing projects like TidalVortex <span class="citation"
 data-cites="mcleanTidalVortexZero2022">(McLean et al. 2022)</span>,
 Gibber <span class="citation"
 data-cites="robertsGibberLiveCoding2012">(Roberts and Kuchera-morin
 2012)</span>, Estuary <span class="citation"
 data-cites="ogbornEstuaryBrowserbasedCollaborative2017">(Ogborn et al.
 2017)</span>, Hydra <span class="citation"
 data-cites="jackHydra2022">(Jack [2022] 2022)</span>, Ocarina <span
 class="citation" data-cites="solomonPurescriptocarina2022">(Solomon
 [2021] 2022)</span> and Feedforward <span class="citation"
 data-cites="mcleanFeedforward2020">(McLean 2020)</span>. This paper
 expands the Strudel Demo paper for the Web Audio Conference 2022 <span
 class="citation" data-cites="StrudelWAC2022">(Roos and McLean
 2022)</span>.</p>
 <p>The first tentative commit to the Strudel project was on 22nd January
 2022 by Alex McLean, with the core representation implemented over the
 following few days. Although this was his first attempt at a
 JavaScript-based application, by 27th January, Alex had managed to
 upload the initial version to the ‘npm’ javascript package database,
 sharing with the wider community for comment. By 4th February, Felix
 Roos had discovered Strudel and contributed a ‘REPL’ user interface to
 it, and then contributed a scheduler the next day, so that Strudel could
 already make sound. At this point, Alex and Felix shared ownership to
 the repository, and the project has since proved to be a productive
 confluence of Felix’s own work into music representation and
 visualisation, with Alex’s experience with making Tidal. Felix has since
 become the primary contributor to Strudel, with Alex continuing to jump
 between developing both Strudel and Tidal. Aspects of Strudel’s
 development have therefore fed back into TidalCycles, and both systems
 have maintained a shared conceptual underpinning. We plan to continue
 working towards feature parity between these systems, although within
 the syntactical trade-offs and library ecosystems of JavaScript and
 Haskell, some divergence is inevitable and healthy.</p>
 <p>Over the first year of its life, Strudel is now a fully-fledged live
 coding environment, porting Tidal’s core represention of patterns,
 pattern transformations, and mininotation for polymetric sequences,
 combined with a wealth of features for synthesising and visualising
 those patterns.</p>
 <h1 data-number="2" id="from-tidal-to-strudel-and-back"><span
 class="header-section-number">2</span> From Tidal to Strudel and
 back</h1>
 <p>As mentioned above, the original Tidal is implemented as a domain
 specific language (DSL) embedded in the Haskell pure functional
 programming language, and takes advantage of Haskell’s terse syntax and
 advanced, ‘strong’ type system. JavaScript on the other hand, is a
 multi-paradigm programming language, with a dynamic type system. Because
 Tidal leans heavily on many of Haskell’s more unique features, it was
 not always clear that it could meaningfully be ported to a
 multi-paradigm scripting language. However, this possibility was already
 demonstrated with an earlier port to Python [TidalVortex; <span
 class="citation" data-cites="mcleanTidalVortexZero2022">McLean et al.
 (2022)</span>], and we have now successfully implemented Tidal’s pure
 functional representation of patterns in Strudel, including partial
 application, currying, and the functor, applicative and monadic
 structures that underlie Tidal’s expressive pattern transformations. The
 result is a terse and highly composable system, where everything is
 either a pattern, or a function for combining and manipulating patterns,
 offering a rich creative ground for exploration.</p>
 <p>This development process has been far from a one-way port, however.
 The process of porting Tidal’s concepts has also opened up new
 possibilities, some just from revisiting every design decision, and some
 from the particular affordances and constraints offered by JavaScript.
 This has lead to new features (and indeed bugfixes) that have found
 their way back to Tidal where appropriate, and ongoing work that we will
 return to in the conclusion of this paper.</p>
 <h1 data-number="3" id="representing-patterns"><span
 class="header-section-number">3</span> Representing Patterns</h1>
 <p>Patterns are the essence of Tidal. Its patterns are abstract entities
 that represent flows of time as functions, adapting a technique called
 pure functional reactive programming. Taking a time span as its input, a
 Pattern can output a set of events that happen within that time span. It
 depends on the structure of the Pattern how the events are located in
 time. From now on, this process of generating events from a time span
 will be called <strong>querying</strong>. Example:</p>
 <div class="sourceCode" id="cb1"><pre class="sourceCode js"><code class="sourceCode javascript"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="kw">const</span> pattern <span class="op">=</span> <span class="fu">sequence</span>(c3<span class="op">,</span> [e3<span class="op">,</span> g3])</span>
 <span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="kw">const</span> events <span class="op">=</span> pattern<span class="op">.</span><span class="fu">queryArc</span>(<span class="dv">0</span><span class="op">,</span> <span class="dv">1</span>)</span>
 <span id="cb1-3"><a href="#cb1-3" aria-hidden="true" tabindex="-1"></a><span class="bu">console</span><span class="op">.</span><span class="fu">log</span>(events<span class="op">.</span><span class="fu">map</span>(e <span class="kw">=&gt;</span> e<span class="op">.</span><span class="fu">show</span>()))</span></code></pre></div>
 <p>In this example, we create a pattern using the <code>sequence</code>
 function and <strong>query</strong> it for the time span from
 <code>0</code> to <code>1</code>. Those numbers represent units of time
 called <strong>cycles</strong>. The length of one cycle depends on the
 tempo, which defaults to one cycle per second. The resulting events
 are:</p>
 <div class="sourceCode" id="cb2"><pre class="sourceCode js"><code class="sourceCode javascript"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a>[{ <span class="dt">value</span><span class="op">:</span> <span class="st">&#39;c3&#39;</span><span class="op">,</span> <span class="dt">begin</span><span class="op">:</span> <span class="dv">0</span><span class="op">,</span> <span class="dt">end</span><span class="op">:</span> <span class="dv">1</span><span class="op">/</span><span class="dv">2</span> }<span class="op">,</span></span>
 <span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a>{ <span class="dt">value</span><span class="op">:</span> <span class="st">&#39;e3&#39;</span><span class="op">,</span> <span class="dt">begin</span><span class="op">:</span> <span class="dv">1</span><span class="op">/</span><span class="dv">2</span><span class="op">,</span> <span class="dt">end</span><span class="op">:</span> <span class="dv">3</span><span class="op">/</span><span class="dv">4</span> }<span class="op">,</span></span>
 <span id="cb2-3"><a href="#cb2-3" aria-hidden="true" tabindex="-1"></a>{ <span class="dt">value</span><span class="op">:</span> <span class="st">&#39;g3&#39;</span><span class="op">,</span> <span class="dt">begin</span><span class="op">:</span> <span class="dv">3</span><span class="op">/</span><span class="dv">4</span><span class="op">,</span> <span class="dt">end</span><span class="op">:</span> <span class="dv">1</span> }]</span></code></pre></div>
 <p>Each event has a value, a begin time and an end time, where time is
 represented as a fraction. In the above case, the events are placed in
 sequential order, where c3 takes the first half, and e3 and g3 together
 take the second half. This temporal placement is the result of the
 <code>sequence</code> function, which divides its arguments equally over
 one cycle. If an argument is an array, the same rule applies to that
 part of the cycle. In the example, e3 and g3 are divided equally over
 the second half of the whole cycle.</p>
 <p>The above examples do not represent how Strudel is used in practice.
 In the live coding editor, the user only has to type in the pattern
 itself, the querying will be handled by the scheduler. The scheduler
 will repeatedly query the pattern for events, which are then scheduled
 as sound synthesis or other event triggers. Also, the above event data
 structure has been simplified for readability.</p>
 <figure>
 <img src="images/strudel-screenshot2.png" style="width:60.0%"
 alt="Screenshot of the Strudel ‘REPL’ live coding editor, including piano-roll visualisation." />
 <figcaption aria-hidden="true">Screenshot of the Strudel ‘REPL’ live
 coding editor, including piano-roll visualisation.</figcaption>
 </figure>
 <h1 data-number="4" id="making-patterns"><span
 class="header-section-number">4</span> Making Patterns</h1>
 <p>In practice, the end-user live coder will not deal with constructing
 patterns directly, but will rather build patterns using Strudel’s
 extensive combinator library to create, combine and transform
 patterns.</p>
 <p>The live coder will rarely use the <code>sequence</code> function as
 seen above, as sequencing is implicit in many functions. For example in
 the following, the <code>note</code> function constructs a pattern of
 notes, sequencing its arguments in the same manner as the previous
 example.</p>
 <div class="sourceCode" id="cb3"><pre class="sourceCode js"><code class="sourceCode javascript"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="fu">note</span>(c3<span class="op">,</span> [e3<span class="op">,</span> g3])</span></code></pre></div>
 <p>Perhaps more often, they will use the mini-notation for even terser
 notation of rhythmic sequences: [^This last example is also valid Tidal
 code, albeit the parenthesis is not required in its Haskell syntax in
 this case. Tidal does not support passing sequences as lists directly to
 the <code>note</code> function, however.].</p>
 <div class="sourceCode" id="cb4"><pre class="sourceCode js"><code class="sourceCode javascript"><span id="cb4-1"><a href="#cb4-1" aria-hidden="true" tabindex="-1"></a><span class="fu">note</span>(<span class="st">&quot;c3 [e3 g3]&quot;</span>)</span></code></pre></div>
 <p>Such sequences are often treated only a starting point for
 manipulation, where they then undergo pattern transformations such as
 repetition, symmetry, interference/combination or randomisation,
 potentially at multiple timescales. Because Strudel patterns are
 represented as pure functions of time rather than as data structures,
 very long and complex generative results can be represented and
 manipulated without having to store the resulting sequences in
 memory.</p>
 <h1 data-number="5" id="pattern-example"><span
 class="header-section-number">5</span> Pattern Example</h1>
 <p>The following example showcases how patterns can be utilized to
 create musical complexity from simple parts, using repetition and
 interference:</p>
 <div class="sourceCode" id="cb5"><pre class="sourceCode js"><code class="sourceCode javascript"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;&lt;0 2 [4 6](3,4,1) 3&gt;&quot;</span></span>
 <span id="cb5-2"><a href="#cb5-2" aria-hidden="true" tabindex="-1"></a><span class="op">.</span><span class="fu">off</span>(<span class="dv">1</span><span class="op">/</span><span class="dv">4</span><span class="op">,</span> <span class="fu">add</span>(<span class="dv">2</span>))</span>
 <span id="cb5-3"><a href="#cb5-3" aria-hidden="true" tabindex="-1"></a><span class="op">.</span><span class="fu">off</span>(<span class="dv">1</span><span class="op">/</span><span class="dv">2</span><span class="op">,</span> <span class="fu">add</span>(<span class="dv">6</span>))</span>
 <span id="cb5-4"><a href="#cb5-4" aria-hidden="true" tabindex="-1"></a><span class="op">.</span><span class="fu">scale</span>(<span class="st">&#39;D minor&#39;</span>)</span>
 <span id="cb5-5"><a href="#cb5-5" aria-hidden="true" tabindex="-1"></a><span class="op">.</span><span class="fu">legato</span>(<span class="op">.</span><span class="dv">25</span>)</span>
 <span id="cb5-6"><a href="#cb5-6" aria-hidden="true" tabindex="-1"></a><span class="op">.</span><span class="fu">note</span>()<span class="op">.</span><span class="fu">s</span>(<span class="st">&quot;sawtooth square&quot;</span>)</span>
 <span id="cb5-7"><a href="#cb5-7" aria-hidden="true" tabindex="-1"></a><span class="op">.</span><span class="fu">delay</span>(<span class="op">.</span><span class="dv">8</span>)<span class="op">.</span><span class="fu">delaytime</span>(<span class="op">.</span><span class="dv">125</span>)</span></code></pre></div>
 <p>The pattern starts with a rhythm of numbers in mini notation, which
 are later interpreted inside the scale of D minor. The first line could
 also be expressed without mini notation:</p>
 <div class="sourceCode" id="cb6"><pre class="sourceCode js"><code class="sourceCode javascript"><span id="cb6-1"><a href="#cb6-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cat</span>(<span class="dv">0</span><span class="op">,</span> <span class="dv">2</span><span class="op">,</span> [<span class="dv">4</span><span class="op">,</span> <span class="dv">6</span>]<span class="op">.</span><span class="fu">euclid</span>(<span class="dv">3</span><span class="op">,</span> <span class="dv">4</span><span class="op">,</span> <span class="dv">1</span>)<span class="op">,</span> <span class="dv">3</span>)</span></code></pre></div>
 <p>These numbers then undergo various pattern transformations. Here is a
 short description of all the functions used:</p>
 <ul>
 <li><code>cat</code>: play elements sequentially, where each lasts one
 cycle</li>
 <li><code>brackets</code>: elements inside brackets are divided equally
 over the time of their parent</li>
 <li><code>.euclid(p, s, o)</code>: place p pulses evenly over s steps,
 with offset o <span class="citation"
 data-cites="toussaintEuclideanAlgorithmGenerates2005">(Toussaint
 2005)</span></li>
 <li><code>.off(n, f)</code>: layers a pattern on top of itself, with the
 new layer offset by n cycles, and with function f applied</li>
 <li><code>.legato(n)</code>: multiply the duration of all events in a
 pattern by a factor of n</li>
 <li><code>.echo(t, n, v)</code>: copy each event t times, with n cycles
 in between each copy, decreasing velocity by v</li>
 <li><code>.note()</code>: interpretes values as notes</li>
 <li><code>.s(name)</code>: play back each event with the given
 sound</li>
 <li><code>.delay(wet)</code>: add delay</li>
 <li><code>.delaytime(t)</code>: set delay time</li>
 </ul>
 <p>Much of the above will be familiar to Tidal users.</p>
 <!-- This example shows some of Strudel's unique support for chords and transposition familiar to students of Western music theory. This differs a little from Tidal's approach and thanks to the integration of the javascript library XXX (*TODO* ? or is this all your work Felix?), Strudel's support for tonal transformations such as voice leading is perhaps respects more advanced than Tidal. -->
 <h1 data-number="6" id="ways-to-make-sound-and-other-events"><span
 class="header-section-number">6</span> Ways to make Sound (and other
 events)</h1>
 <p>To generate sound, Strudel supports bindings for different
 outputs:</p>
 <ul>
 <li>Tone.js (deprecated)</li>
 <li>Web Audio API</li>
 <li>WebDirt, a js recreation of Tidal’s <em>Dirt</em> sample engine
 (deprecated)</li>
 <li>OSC via osc-js, compatible with superdirt</li>
 <li>Csound via the Csound WebAssembly build</li>
 <li>MIDI via WebMIDI</li>
 <li>Serial via WebSerial</li>
 </ul>
 <p>At first, we used Tone.js as sound output, but it proved to be
 limited for the use case of Strudel, where each individual event could
 potentially have a completely different audio graph. While the Web Audio
 API takes a <em>fire-and-forget</em> approach, creating a lot of Tone.js
 instruments and effects causes performance issues quickly. For that
 reason, we chose to search for alternatives.</p>
 <p>Strudel’s new default output uses the Web Audio API to create a new
 audio graph for each event. It currently supports basic oscillators,
 sample playback, various effects and an experimental support for
 soundfonts.</p>
 <p>WebDirt <span class="citation"
 data-cites="ogbornDktr0WebDirt2022">(Ogborn [2016] 2022)</span> was
 created as part of the Estuary Live Coding System <span class="citation"
 data-cites="ogbornEstuaryBrowserbasedCollaborative2017">(Ogborn et al.
 2017)</span>, and proved to be a solid choice for handling samples in
 Strudel as well. We are however focused on working more directly with
 the Web Audio API to be able to integrate new features more tightly.</p>
 <p>Using the OSC protocol via Strudel’s provided Node.js-based OSC proxy
 server, it is possible to send network messages to trigger events. This
 is mainly used to render sound using SuperDirt <span class="citation"
 data-cites="SuperDirt2022">(<em>SuperDirt</em> [2015] 2022)</span>,
 which is the well-developed Supercollider-based synthesis framework that
 Tidal live coders generally use as standard.</p>
 <p>Recently, the experimental integration of Csound proved to bring a
 new dimension of sound design capabilities to Strudel. Thanks to the
 WebAssembly distribution of this classic system <span class="citation"
 data-cites="CsoundWebAssembly">(Yi, Lazzarini, and Costello
 2018)</span>, Csound ‘orchestra’ synthesisers can be embedded in and
 then patterned with Strudel code.</p>
 <p>MIDI output can also be used to send MIDI messages to either external
 instruments or to other programs on the same device. Unlike OSC, Strudel
 is able to send MIDI directly without requiring additional proxy
 software, but only from web browsers that support it (at the time of
 writing, this means Chromium-based browsers).</p>
 <p>Finally, Strudel supports Serial output, for example to trigger
 events via microcontrollers. This has already been explored for robot
 choreography by Kate Sicchio and Alex McLean, via a performance
 presented at the International Conference on Live Interfaces 2022.</p>
 <h1 data-number="7" id="the-strudel-repl"><span
 class="header-section-number">7</span> The Strudel REPL</h1>
 <p>While Strudel can be used as a library in any JavaScript codebase,
 its main, reference user interface is the Strudel REPL[^REPL stands for
 read, evaluate, print/play, loop. It is friendly jargon for an
 interactive programming interface from computing heritage, usually for a
 commandline interface but also applied to live coding editors.], which
 is a browser-based live coding environment. This live code editor is
 dedicated to manipulating Strudel patterns while they play. The REPL
 features built-in visual feedback, which highlights which elements in
 the patterned (mini-notation) sequences are influencing the event that
 is currently being played. This feedback is designed to support both
 learning and live use of Strudel.</p>
 <p>Besides a UI for playback control and meta information, the main part
 of the REPL interface is the code editor powered by CodeMirror. In it,
 the user can edit and evaluate pattern code live, using one of the
 available synthesis outputs to create music and/or sound art. The
 control flow of the REPL follows 3 basic steps:</p>
 <ol type="1">
 <li>The user writes and updates code. Each update transpiles and
 evaluates it to create a <code>Pattern</code> instance</li>
 <li>While the REPL is running, the <code>Scheduler</code> queries the
 active <code>Pattern</code> by a regular interval, generating
 <code>Events</code> (also known as <code>Haps</code> in Strudel) for the
 next time span.</li>
 <li>For each scheduling tick, all generated <code>Events</code> are
 triggered by calling their <code>onTrigger</code> method, which is set
 by the output.</li>
 </ol>
 <figure>
 <img
 src="https://github.com/tidalcycles/strudel/raw/talk/talk/public/strudelflow.png?raw=true"
 style="width:43.0%" alt="REPL control flow" />
 <figcaption aria-hidden="true">REPL control flow</figcaption>
 </figure>
 <h2 data-number="7.1" id="user-code"><span
 class="header-section-number">7.1</span> User Code</h2>
 <p>To create a <code>Pattern</code> from the user code, two steps are
 needed:</p>
 <ol type="1">
 <li>Transpile the JS input code to make it functional</li>
 <li>Evaluate the transpiled code</li>
 </ol>
 <h3 data-number="7.1.1" id="transpilation-evaluation"><span
 class="header-section-number">7.1.1</span> Transpilation &amp;
 Evaluation</h3>
 <p>In the JavaScript world, using transpilation is a common practise to
 be able to use language features that are not supported by the base
 language. Tools like <code>babel</code> will transpile code that
 contains unsupported language features into a version of the code
 without those features.</p>
 <p>In the same tradition, Strudel can add a transpilation step to
 simplify the user code in the context of live coding. For example, the
 Strudel REPL lets the user create mini notation patterns using just
 double quoted strings, while single quoted strings remain what they
 are:</p>
 <div class="sourceCode" id="cb7"><pre class="sourceCode js"><code class="sourceCode javascript"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;c3 [e3 g3]*2&quot;</span></span></code></pre></div>
 <p>is transpiled to:</p>
 <div class="sourceCode" id="cb8"><pre class="sourceCode js"><code class="sourceCode javascript"><span id="cb8-1"><a href="#cb8-1" aria-hidden="true" tabindex="-1"></a><span class="fu">mini</span>(<span class="st">&quot;c3 [e3 g3]*2&quot;</span>)<span class="op">.</span><span class="fu">withMiniLocation</span>([<span class="dv">1</span><span class="op">,</span><span class="dv">0</span><span class="op">,</span><span class="dv">0</span>]<span class="op">,</span>[<span class="dv">1</span><span class="op">,</span><span class="dv">14</span><span class="op">,</span><span class="dv">14</span>])</span></code></pre></div>
 <p>Here, the string is wrapped in <code>mini</code>, which will create a
 pattern from a mini notation string. Additionally, the
 <code>withMiniLocation</code> method passes the original source code
 location of the string to the pattern, which enables highlighting active
 events.</p>
 <p>Other convenient features like pseudo variables, operator overloading
 and top level await are possible with transpilation.</p>
 <p>After the transpilation, the code is ready to be evaluated into a
 <code>Pattern</code>.</p>
 <p>Behind the scenes, the user code string is parsed with
 <code>acorn</code>, turning it into an Abstract Syntax Tree (AST). The
 AST allows changing the structure of the code before generating the
 transpiled version using <code>escodegen</code>.</p>
 <h3 data-number="7.1.2" id="mini-notation"><span
 class="header-section-number">7.1.2</span> Mini Notation</h3>
 <p>While the transpilation allows JavaScript to express Patterns in a
 less verbose way, it is still preferable to use the Mini Notation as a
 more compact way to express rhythm. Strudel aims to provide the same
 Mini Notation features and syntax as used in Tidal.</p>
 <p>The Mini Notation parser is implemented using <code>peggy</code>,
 which allows generating performant parsers for Domain Specific Languages
 (DSLs) using a concise grammar notation. The generated parser turns the
 Mini Notation string into an AST which is used to call the respective
 Strudel functions with the given structure. For example,
 <code>"c3 [e3 g3]*2"</code> will result in the following calls:</p>
 <div class="sourceCode" id="cb9"><pre class="sourceCode js"><code class="sourceCode javascript"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="fu">seq</span>(</span>
 <span id="cb9-2"><a href="#cb9-2" aria-hidden="true" tabindex="-1"></a>  <span class="fu">reify</span>(<span class="st">&#39;c3&#39;</span>)<span class="op">.</span><span class="fu">withLocation</span>([<span class="dv">1</span><span class="op">,</span><span class="dv">1</span><span class="op">,</span><span class="dv">1</span>]<span class="op">,</span> [<span class="dv">1</span><span class="op">,</span><span class="dv">4</span><span class="op">,</span><span class="dv">4</span>])<span class="op">,</span></span>
 <span id="cb9-3"><a href="#cb9-3" aria-hidden="true" tabindex="-1"></a>  <span class="fu">seq</span>(</span>
 <span id="cb9-4"><a href="#cb9-4" aria-hidden="true" tabindex="-1"></a>    <span class="fu">reify</span>(<span class="st">&#39;e3&#39;</span>)<span class="op">.</span><span class="fu">withLocation</span>([<span class="dv">1</span><span class="op">,</span><span class="dv">5</span><span class="op">,</span><span class="dv">5</span>]<span class="op">,</span> [<span class="dv">1</span><span class="op">,</span><span class="dv">8</span><span class="op">,</span><span class="dv">8</span>])<span class="op">,</span></span>
 <span id="cb9-5"><a href="#cb9-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">reify</span>(<span class="st">&#39;g3&#39;</span>)<span class="op">.</span><span class="fu">withLocation</span>([<span class="dv">1</span><span class="op">,</span><span class="dv">8</span><span class="op">,</span><span class="dv">8</span>]<span class="op">,</span> [<span class="dv">1</span><span class="op">,</span><span class="dv">10</span><span class="op">,</span><span class="dv">10</span>])<span class="op">,</span></span>
 <span id="cb9-6"><a href="#cb9-6" aria-hidden="true" tabindex="-1"></a>  )<span class="op">.</span><span class="fu">fast</span>(<span class="dv">2</span>)</span>
 <span id="cb9-7"><a href="#cb9-7" aria-hidden="true" tabindex="-1"></a>)</span></code></pre></div>
 <h3 data-number="7.1.3" id="highlighting-locations"><span
 class="header-section-number">7.1.3</span> Highlighting Locations</h3>
 <p>As seen in the examples above, both the JS and the Mini Notation
 parser add source code locations using <code>withMiniLocation</code> and
 <code>withLocation</code> methods. While the JS parser adds locations
 relative to the user code as a whole, the Mini Notation adds locations
 relative to the position of the mini notation string. The absolute
 location of elements within Mini Notation can be calculated by simply
 adding both locations together. This absolute location can be used to
 highlight active events in real time.</p>
 <h2 data-number="7.2" id="scheduling-events"><span
 class="header-section-number">7.2</span> Scheduling Events</h2>
 <p>After an instance of <code>Pattern</code> is obtained from the user
 code, it is used by the scheduler to get queried for events. Once
 started, the scheduler runs at a fixed interval to query active pattern
 for events withing the current interval’s time span. A simplified
 implementation looks like this:</p>
 <div class="sourceCode" id="cb10"><pre
 class="sourceCode js"><code class="sourceCode javascript"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="kw">let</span> pattern <span class="op">=</span> <span class="fu">seq</span>(<span class="st">&#39;c3&#39;</span><span class="op">,</span> [<span class="st">&#39;e3&#39;</span><span class="op">,</span> <span class="st">&#39;g3&#39;</span>])<span class="op">;</span> <span class="co">// pattern from user</span></span>
 <span id="cb10-2"><a href="#cb10-2" aria-hidden="true" tabindex="-1"></a><span class="kw">let</span> interval <span class="op">=</span> <span class="fl">0.5</span><span class="op">;</span> <span class="co">// query interval in seconds</span></span>
 <span id="cb10-3"><a href="#cb10-3" aria-hidden="true" tabindex="-1"></a><span class="kw">let</span> time <span class="op">=</span> <span class="dv">0</span><span class="op">;</span> <span class="co">// beginning of current time span</span></span>
 <span id="cb10-4"><a href="#cb10-4" aria-hidden="true" tabindex="-1"></a><span class="kw">let</span> minLatency <span class="op">=</span> <span class="op">.</span><span class="dv">1</span><span class="op">;</span> <span class="co">// min time before a hap should trigger</span></span>
 <span id="cb10-5"><a href="#cb10-5" aria-hidden="true" tabindex="-1"></a><span class="pp">setInterval</span>(() <span class="kw">=&gt;</span> {</span>
 <span id="cb10-6"><a href="#cb10-6" aria-hidden="true" tabindex="-1"></a>  <span class="kw">const</span> haps <span class="op">=</span> pattern<span class="op">.</span><span class="fu">queryArc</span>(time<span class="op">,</span> time <span class="op">+</span> interval)<span class="op">;</span></span>
 <span id="cb10-7"><a href="#cb10-7" aria-hidden="true" tabindex="-1"></a>  time <span class="op">+=</span> interval<span class="op">;</span> <span class="co">// increment time</span></span>
 <span id="cb10-8"><a href="#cb10-8" aria-hidden="true" tabindex="-1"></a>  haps<span class="op">.</span><span class="fu">forEach</span>((hap) <span class="kw">=&gt;</span> {</span>
 <span id="cb10-9"><a href="#cb10-9" aria-hidden="true" tabindex="-1"></a>    <span class="kw">const</span> deadline <span class="op">=</span> hap<span class="op">.</span><span class="at">whole</span><span class="op">.</span><span class="at">begin</span> <span class="op">-</span> time <span class="op">+</span> minLatency<span class="op">;</span></span>
 <span id="cb10-10"><a href="#cb10-10" aria-hidden="true" tabindex="-1"></a>    <span class="fu">onTrigger</span>(hap<span class="op">,</span> deadline<span class="op">,</span> duration)<span class="op">;</span></span>
 <span id="cb10-11"><a href="#cb10-11" aria-hidden="true" tabindex="-1"></a>  })<span class="op">;</span></span>
 <span id="cb10-12"><a href="#cb10-12" aria-hidden="true" tabindex="-1"></a>}<span class="op">,</span> interval <span class="op">*</span> <span class="dv">1000</span>)<span class="op">;</span> <span class="co">// query each &quot;interval&quot; seconds</span></span></code></pre></div>
 <p>Note that the above code is simplified for illustrative purposes. The
 actual implementation has to work around imprecise callbacks of
 <code>setInterval</code>. More about the implementation details can be
 read in <a
 href="https://loophole-letters.vercel.app/web-audio-scheduling">this
 blog post</a>.</p>
 <p>The fact that <code>Pattern.queryArc</code> is a pure function that
 maps a time span to a set of events allows us to choose any interval we
 like without changing the resulting output. It also means that when the
 pattern is changed from outside, the next scheduling callback will work
 with the new pattern, keeping its clock running.</p>
 <p>The latency between the time the pattern is evaluated and the change
 is heard is between <code>minLatency</code> and
 <code>interval + minLatency</code>, in our example between 100ms and
 600ms. In Strudel, the current query interval is 50ms with a minLatency
 of 100ms, meaning the latency is between 50ms and 150ms.</p>
 <h2 data-number="7.3" id="output"><span
 class="header-section-number">7.3</span> Output</h2>
 <p>The last step is to trigger each event in the chosen output. This is
 where the given time and value of each event is used to generate audio
 or any other form of time based output. The default output of the
 Strudel REPL is the WebAudio output. To understand what an output does,
 we first have to understand what control parameters are.</p>
 <h3 data-number="7.3.1" id="control-parameters"><span
 class="header-section-number">7.3.1</span> Control Parameters</h3>
 <p>To be able to manipulate multiple aspects of sound in parallel, so
 called control parameters are used to shape the value of each event.
 Example:</p>
 <div class="sourceCode" id="cb11"><pre
 class="sourceCode js"><code class="sourceCode javascript"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="fu">note</span>(<span class="st">&quot;c3 e3&quot;</span>)<span class="op">.</span><span class="fu">cutoff</span>(<span class="dv">1000</span>)<span class="op">.</span><span class="fu">s</span>(<span class="st">&#39;sawtooth&#39;</span>)</span>
 <span id="cb11-2"><a href="#cb11-2" aria-hidden="true" tabindex="-1"></a>  <span class="op">.</span><span class="fu">queryArc</span>(<span class="dv">0</span><span class="op">,</span> <span class="dv">1</span>)<span class="op">.</span><span class="fu">map</span>(hap <span class="kw">=&gt;</span> hap<span class="op">.</span><span class="at">value</span>)</span>
 <span id="cb11-3"><a href="#cb11-3" aria-hidden="true" tabindex="-1"></a><span class="co">/* [</span></span>
 <span id="cb11-4"><a href="#cb11-4" aria-hidden="true" tabindex="-1"></a><span class="co">  { note: &#39;c3&#39;, cutoff: 1000, s: &#39;sawtooth&#39; }</span></span>
 <span id="cb11-5"><a href="#cb11-5" aria-hidden="true" tabindex="-1"></a><span class="co">  { note: &#39;e3&#39;, cutoff: 1000, s: &#39;sawtooth&#39; }</span></span>
 <span id="cb11-6"><a href="#cb11-6" aria-hidden="true" tabindex="-1"></a><span class="co">] */</span></span></code></pre></div>
 <p>Here, the control parameter functions <code>note</code>,
 <code>cutoff</code> and <code>s</code> are used, where each controls a
 different property in the value object. Each control parameter function
 accepts a primitive value, a list of values to be sequenced into a
 <code>Pattern</code>, or a <code>Pattern</code>. In the example,
 <code>note</code> gets a <code>Pattern</code> from a Mini Notation
 expression (double quoted), while <code>cutoff</code> and <code>s</code>
 are given a <code>Number</code> and a (single quoted)
 <code>String</code> respectively.</p>
 <p>Strudel comes with a large default set of control parameter functions
 that are based on the ones used by Tidal and SuperDirt, focusing on
 music and audio terminology. It is however possible to create custom
 control paramters for any purpose:</p>
 <div class="sourceCode" id="cb12"><pre
 class="sourceCode js"><code class="sourceCode javascript"><span id="cb12-1"><a href="#cb12-1" aria-hidden="true" tabindex="-1"></a><span class="kw">const</span> { x<span class="op">,</span> y } <span class="op">=</span> <span class="fu">createParams</span>(<span class="st">&#39;x&#39;</span><span class="op">,</span> <span class="st">&#39;y&#39;</span>)</span>
 <span id="cb12-2"><a href="#cb12-2" aria-hidden="true" tabindex="-1"></a><span class="fu">x</span>(sine<span class="op">.</span><span class="fu">range</span>(<span class="dv">0</span><span class="op">,</span> <span class="dv">200</span>))<span class="op">.</span><span class="fu">y</span>(cosine<span class="op">.</span><span class="fu">range</span>(<span class="dv">0</span><span class="op">,</span><span class="dv">200</span>))</span></code></pre></div>
 <p>This example creates the custom control parameters <code>x</code> and
 <code>y</code> which are then used to form a pattern that descibes the
 coordinates of a circle.</p>
 <h3 data-number="7.3.2" id="outputs"><span
 class="header-section-number">7.3.2</span> Outputs</h3>
 <p>Now that we know how the value of an event is manipulated using
 control parameters, we can look at how outputs can use that value to
 generate anything. The scheduler above was calling the
 <code>onTrigger</code> function which is used to implement the output. A
 very simple version of the web audio output could look like this:</p>
 <div class="sourceCode" id="cb13"><pre
 class="sourceCode js"><code class="sourceCode javascript"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="kw">function</span> <span class="fu">onTrigger</span>(hap<span class="op">,</span> deadline<span class="op">,</span> duration) {</span>
 <span id="cb13-2"><a href="#cb13-2" aria-hidden="true" tabindex="-1"></a>  <span class="kw">const</span> { note } <span class="op">=</span> hap<span class="op">.</span><span class="at">value</span><span class="op">;</span></span>
 <span id="cb13-3"><a href="#cb13-3" aria-hidden="true" tabindex="-1"></a>  <span class="kw">const</span> time <span class="op">=</span> <span class="fu">getAudioContext</span>()<span class="op">.</span><span class="at">currentTime</span> <span class="op">+</span> deadline<span class="op">;</span></span>
 <span id="cb13-4"><a href="#cb13-4" aria-hidden="true" tabindex="-1"></a>  <span class="kw">const</span> o <span class="op">=</span> <span class="fu">getAudioContext</span>()<span class="op">.</span><span class="fu">createOscillator</span>()<span class="op">;</span></span>
 <span id="cb13-5"><a href="#cb13-5" aria-hidden="true" tabindex="-1"></a>  o<span class="op">.</span><span class="at">frequency</span><span class="op">.</span><span class="at">value</span> <span class="op">=</span> <span class="fu">getFreq</span>(note)<span class="op">;</span></span>
 <span id="cb13-6"><a href="#cb13-6" aria-hidden="true" tabindex="-1"></a>  o<span class="op">.</span><span class="fu">start</span>(time)<span class="op">;</span></span>
 <span id="cb13-7"><a href="#cb13-7" aria-hidden="true" tabindex="-1"></a>  o<span class="op">.</span><span class="fu">stop</span>(time <span class="op">+</span> <span class="bu">event</span><span class="op">.</span><span class="at">duration</span>)<span class="op">;</span></span>
 <span id="cb13-8"><a href="#cb13-8" aria-hidden="true" tabindex="-1"></a>  o<span class="op">.</span><span class="fu">connect</span>(<span class="fu">getAudioContext</span>()<span class="op">.</span><span class="at">destination</span>)<span class="op">;</span></span>
 <span id="cb13-9"><a href="#cb13-9" aria-hidden="true" tabindex="-1"></a>}</span></code></pre></div>
 <p>The above example will create an <code>OscillatorNode</code> for each
 event, where the frequency is controlled by the <code>note</code> param.
 In essence, this is how the WebAudio API output of Strudel works, only
 with many more parameters to control synths, samples and effects.</p>
 <h1 data-number="8" id="pattern-alignment-and-combination"><span
 class="header-section-number">8</span> Pattern alignment and
 combination</h1>
 <p>One core aspect of Strudel, inherited from Tidal, is the flexible way
 that patterns can be combined, irrespective of their structure. Its
 declarative approach means a live coder does not have to think about the
 details of <em>how</em> this is done, only <em>what</em> is to be
 done.</p>
 <p>As a simple example, consider two number patterns
 <code>"0 [1 2] 3"</code>, and <code>"10 20"</code>. The first has three
 contiguous steps of equal lengths, with the second step broken down into
 two substeps, giving four events in total. There are a very large number
 of ways in which the structure of these two patterns could be combined,
 but the default method in both Strudel and Tidal is to line up the
 cycles of the two patterns, and then take events from the first pattern
 and match them with those in the second pattern. Therefore, the
 following two lines are equivalent:</p>
 <div class="sourceCode" id="cb14"><pre
 class="sourceCode js"><code class="sourceCode javascript"><span id="cb14-1"><a href="#cb14-1" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;0 [1 2] 3&quot;</span><span class="op">.</span><span class="fu">add</span>(<span class="st">&quot;10 20&quot;</span>)</span>
 <span id="cb14-2"><a href="#cb14-2" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;10 [11 22] 23&quot;</span></span></code></pre></div>
 <p>Where the events only partially overlap, they are treated as
 fragments of the event in the first pattern. This is a little difficult
 to conceptualise, but lets start by comparing the two patterns in the
 following example:</p>
 <div class="sourceCode" id="cb15"><pre
 class="sourceCode js"><code class="sourceCode javascript"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;0 1 2&quot;</span><span class="op">.</span><span class="fu">add</span>(<span class="st">&quot;10 20&quot;</span>)</span>
 <span id="cb15-2"><a href="#cb15-2" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;10 [11 21] 20&quot;</span></span></code></pre></div>
 <p>They are similar to the previous example in that the number
 <code>1</code> is split in two, with its two halves added to
 <code>10</code> and <code>20</code> respectively. However, the
 <code>11</code> ‘remembers’ that it is a fragment of that original
 <code>1</code> event, and so is treated as having a duration of a third
 of a cycle, despite only being active for a sixth of a cycle. Likewise,
 the <code>21</code> is also a fragment of that original <code>1</code>
 event, but a fragment of its second half. Because the start of its event
 is missing, it wouldn’t actually trigger a sound (unless it underwent
 further pattern transformations/combinations).</p>
 <p>In practice, the effect of this default, implicit method for
 combining two patterns is that the second pattern is added <em>in</em>
 to the first one, and indeed this can be made explicit:</p>
 <div class="sourceCode" id="cb16"><pre
 class="sourceCode js"><code class="sourceCode javascript"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="st">&quot;0 1 2&quot;</span><span class="op">.</span><span class="at">add</span><span class="op">.</span><span class="fu">in</span>(<span class="st">&quot;10 20&quot;</span>)</span></code></pre></div>
 <p>This makes way for other ways to align the pattern, and several are
 already defined, in particular:</p>
 <ul>
 <li><code>in</code> - as explained above, aligns cycles, and applies
 values from the pattern on the right <em>in</em> to the pattern on the
 left.</li>
 <li><code>out</code> - as with <code>in</code>, but values are applied
 <em>out</em> of the pattern on the left (i.e. <em>in</em> to the one on
 the right).</li>
 <li><code>mix</code> - structures from both patterns are combined, so
 that the new events are not fragments but are created at intersections
 of events from both sides.</li>
 <li><code>squeeze</code> - cycles from the pattern on the right are
 squeezed into events on the left. So that
 e.g. <code>"0 1 2".add.squeeze("10 20")</code> is equivalent to
 <code>"[10 20] [11 21] [12 22]"</code>.</li>
 <li><code>squeezeout</code> - as with <code>squeeze</code>, but cycles
 from the left are squeezed into events on the right. So,
 <code>"0 1 2".add.squeezeout("10 20")</code> is equivalent to
 <code>[10 11 12] [20 21 22]</code>.</li>
 <li><code>trig</code> is similar to <code>squeezeout</code> in that
 cycles from the right are aligned with events on the left. However those
 cycles are not ‘squeezed’, rather they are truncated to fit the event.
 So <code>"0 1 2 3 4 5 6 7".add.trig("10 [20 30]")</code> would be
 equivalent to <code>10 11 12 13 20 21 30 31</code>. In effect, events on
 the right ‘trigger’ cycles on the left.</li>
 <li><code>trigzero</code> is similar to <code>trig</code>, but the
 pattern is ‘triggered’ from its very first cycle, rather than from the
 current cycle. <code>trig</code> and <code>trigzero</code> therefore
 only give different results where the leftmost pattern differs from one
 cycle to the next.</li>
 </ul>
 <p>We will save going deeper into the background, design and
 practicalities of these alignment functions for future publications.
 However in the next section, we take them as a case study for looking at
 the different design affordances offered by Haskell to Tidal, and
 JavaScript to Strudel.</p>
 <h1 data-number="9" id="comparing-strudel-and-haskell-in-use"><span
 class="header-section-number">9</span> Comparing Strudel and Haskell in
 use</h1>
 <p>Unlike Haskell, JavaScript lacks the ability to define custom infix
 operators, or change the meaning of existing ones. So the above Strudel
 example of <code>"0 1 2".add.out("10 20")</code> is equivalent to the
 Tidal expression <code>"0 1 2" +| "10 20"</code>, where the vertical bar
 in the operator <code>+|</code> stands for <code>out</code> (where
 <code>a |+ b</code> would be equivalent of
 <code>a.add.in(b)</code>).</p>
 <p>From this we can already see that Tidal tends towards brevity through
 mixing infix operators with functions, and Strudel tends towards
 spelling out operations which are joined together with the
 <code>.</code> operator. This then is the design trade-off of Tidal’s
 tersity, versus Strudel’s simplicity.</p>
 <p>To demonstrate this, consider the following Tidal pattern:</p>
 <pre class="tidal"><code>iter 4 $ every 3 (||+ n &quot;10 20&quot;) $ (n &quot;0 1 3&quot;) # s &quot;triangle&quot; # crush 4</code></pre>
 <p>This can be directly translated to the Strudel equivalent:</p>
 <div class="sourceCode" id="cb18"><pre
 class="sourceCode js"><code class="sourceCode javascript"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="fu">iter</span>(<span class="dv">4</span><span class="op">,</span> <span class="fu">every</span>(<span class="dv">3</span><span class="op">,</span> add<span class="op">.</span><span class="fu">squeeze</span>(<span class="st">&quot;10 20&quot;</span>)<span class="op">,</span> <span class="fu">n</span>(<span class="st">&quot;0 1 3&quot;</span>)<span class="op">.</span><span class="fu">s</span>(<span class="st">&quot;triangle&quot;</span>)<span class="op">.</span><span class="fu">crush</span>(<span class="dv">4</span>)))</span></code></pre></div>
 <p>Although for a more canonical Strudel expression, we would reorder it
 as:</p>
 <div class="sourceCode" id="cb19"><pre
 class="sourceCode js"><code class="sourceCode javascript"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="fu">n</span>(<span class="st">&quot;0 1 3&quot;</span>)<span class="op">.</span><span class="fu">every</span>(<span class="dv">3</span><span class="op">,</span> add<span class="op">.</span><span class="fu">squeeze</span>(<span class="st">&quot;10 20&quot;</span>))<span class="op">.</span><span class="fu">iter</span>(<span class="dv">4</span>)<span class="op">.</span><span class="fu">s</span>(<span class="st">&quot;triangle&quot;</span>)<span class="op">.</span><span class="fu">crush</span>(<span class="dv">4</span>)</span></code></pre></div>
 <p>The Strudel example uses the <code>.</code> method call operator for
 all operations and combinations, whereas the Tidal example has
 <code>#</code> for the default method for combining patterns and uses
 infix operators for other methods. The lack of parenthesis in the Tidal
 example is partly due to the way that arguments are applied to Haskell’s
 functions, and partly due to the use of the <code>$</code> operator as
 an alternative way to establish precedence and control the order of
 evaluation.</p>
 <p>Considering the above, we argue that the Haskell syntax is a little
 cleaner, but that the Strudel syntax is easier to learn. Our informal
 observation is that while Haskell’s dollar <code>$</code> operator is
 very useful in making code easier to work with, it is one of the most
 difficult aspects of Tidal use for beginners to learn. On the other
 hand, the deeper levels of parenthesis in Strudel code can be difficult
 to keep track of, especially while coding under pressure of live musical
 performance. However this difficulty can be largely be mitigated by
 reordering expressions, and further mitigated by supporting editor
 features.</p>
 <p>With Strudel, we have little choice but to embrace the affordances
 and constraints offered by JavaScript, and while designing a
 domain-specific language entirely based on method calls is a challenge,
 through creative adoption of functional programming techniques like
 partial application, we are so far very happy with the results. Tidal’s
 functional reactive approach to pattern-making has in general translated
 well to JavaScript, and opportunities and constraints have overall
 traded off to create a very approachable and useable live coding
 environment.</p>
 <h2 data-number="9.1" id="the-trade-off-of-flexible-typing"><span
 class="header-section-number">9.1</span> The trade-off of flexible
 typing</h2>
 <p>We have identified one problem with porting Tidal to JavaScript where
 we have missed Haskell’s strict typing and type inference. In both Tidal
 and Strudel, time is rational, where any point in time is represented as
 the ratio of two integers. This allows representation of musical ratios
 such that are impossible to represent accurately using the more common
 floating point numbers. However while libraries are available that
 support rational numbers in JavaScript, the lack of strict typing means
 that it is easy to implement pattern methods where computationally
 expensive conversion from floating point to rational numbers are
 performed late, and therefore often enough to overload the CPUs, due to
 the large number of iterative calculations required to estimate a ratio
 for a given floating point number. To mitigate this problem, we might
 consider moving to TypeScript in the future.</p>
 <h1 data-number="10" id="future-outlook"><span
 class="header-section-number">10</span> Future Outlook</h1>
 <p>The project is still young, with many features on the horizon. As
 general guiding principles, Strudel aims to be</p>
 <ol type="1">
 <li>accessible</li>
 <li>consistent with Tidal’s approach to pattern</li>
 <li>modular and extensible</li>
 </ol>
 <p>While Haskell’s type system makes it a great language for the ongoing
 development of Tidal’s inner representation of pattern, JavaScript’s
 vibrant ecosystem, flexibility and accessibility makes it a great host
 for more ad-hoc experiments, including interface design. For the future,
 it is planned to integrate additional alternative sound engines such as
 Glicol <span class="citation" data-cites="lanChaosprintGlicol2022">(Lan
 [2020] 2022)</span> and Faust <span class="citation"
 data-cites="FaustProgrammingLanguage2022">(<em>Faust - Programming
 Language for Audio Applications and Plugins</em> [2016] 2022)</span>.
 Strudel is already approaching feature parity with Tidal, but there are
 more Tidal functions to be ported, and work to be done to improve
 compatibility with Tidal’s mininotation. Tidal version 2.0 is under
 development, which brings a new representation for sequences to its
 patterns, which will then be brought to Strudel. Besides sound, other
 ways to render events are being explored, such as graphical, and
 choreographic output. We are also looking into alternative ways of
 editing patterns, including multi-user editing for network music,
 parsing a novel syntax to escape the constraints of javascript, and
 developing hardware/e-textile interfaces. In summary, there is a lot of
 fun ahead.</p>
 <h1 data-number="11" id="links"><span
 class="header-section-number">11</span> Links</h1>
 <p>The Strudel REPL is available at <a
 href="https://strudel.cc"
 class="uri">https://strudel.cc</a>, including an
 interactive tutorial. The repository is at <a
 href="https://github.com/tidalcycles/strudel"
 class="uri">https://github.com/tidalcycles/strudel</a>, all the code is
 open source under the AGPL-3.0 License.</p>
 <h1 data-number="12" id="acknowledgments"><span
 class="header-section-number">12</span> Acknowledgments</h1>
 <p>Thanks to the Strudel and wider Tidal, live coding, WebAudio and
 free/open source software communities for inspiration and support. Alex
 McLean’s work on this project is supported by a UKRI Future Leaders
 Fellowship [grant number MR/V025260/1].</p>
 <h1 class="unnumbered" id="references">References</h1>
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 </div>
 <div id="ref-SuperDirt2022" class="csl-entry" role="doc-biblioentry">
 <em>SuperDirt</em>. (2015) 2022. SuperCollider. musikinformatik. <a
 href="https://github.com/musikinformatik/SuperDirt">https://github.com/musikinformatik/SuperDirt</a>.
 </div>
 <div id="ref-toussaintEuclideanAlgorithmGenerates2005" class="csl-entry"
 role="doc-biblioentry">
 Toussaint, Godfried. 2005. <span>“The Euclidean Algorithm Generates
 Traditional Musical Rhythms.”</span> In <em>In Proceedings of BRIDGES:
 Mathematical Connections in Art, Music and Science</em>, 47–56. <a
 href="http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.62.231">http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.62.231</a>.
 </div>
 <div id="ref-CsoundWebAssembly" class="csl-entry"
 role="doc-biblioentry">
 Yi, Steven, Victor Lazzarini, and Edward Costello. 2018.
 <span>“WebAssembly AudioWorklet Csound.”</span> In. Berlin, Germany. <a
 href="https://mural.maynoothuniversity.ie/16018/">https://mural.maynoothuniversity.ie/16018/</a>.
 </div>
 </div>
 </body>
 </html>
@@ -1,80 +0,0 @@
 $if(false)$
 This is a pandoc template and should not be edited.
 $endif$
 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 <html xmlns="http://www.w3.org/1999/xhtml"$if(lang)$ lang="$lang$" xml:lang="$lang$"$endif$>
 <head>
  <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
  <meta http-equiv="Content-Style-Type" content="text/css" />
  <meta name="generator" content="pandoc" />
 $for(author-meta)$
  <meta name="author" content="$author-meta$" />
 $endfor$
 $if(date-meta)$
  <meta name="date" content="$date-meta$" />
 $endif$
  <title>$if(title-prefix)$$title-prefix$ - $endif$$pagetitle$</title>
  <style type="text/css">code{white-space: pre;}</style>
 $if(quotes)$
  <style type="text/css">q { quotes: "“" "”" "‘" "’"; }</style>
 $endif$
 $if(highlighting-css)$
  <style type="text/css">
 $highlighting-css$
  </style>
 $endif$
  <link rel="stylesheet" href="css/iclc.css" $if(html5)$$else$type="text/css" $endif$/>
 $for(css)$
  <link rel="stylesheet" href="$css$" $if(html5)$$else$type="text/css" $endif$/>
 $endfor$
 $if(math)$
  $math$
 $endif$
 $for(header-includes)$
  $header-includes$
 $endfor$
 </head>
 <body>
 $for(include-before)$
 $include-before$
 $endfor$
 $if(title)$
 <div id="$idprefix$header">
 <h1 class="title">$title$</h1>
 $if(subtitle)$
 <h1 class="subtitle">$subtitle$</h1>
 $endif$
 <ul id="authorlist">
 $for(author)$
 <li>$author$</li>
 $endfor$
 </ul>
 $if(date)$
 <h3 class="date">$date$</h3>
 $endif$
 </div>
 $endif$
 $if(toc)$
 <div id="$idprefix$TOC">
 $toc$
 </div>
 $endif$
 <h2 class="abstract">Abstract</h2>
 <div id="abstract">
 $if(abstract)$
 $abstract$
 $else$
 Please provide an abstract in the metadata block at the top of your
 markdown document. Refer to template.txt for details.
 $endif$
 </div>
 $body$
 $for(include-after)$
 $include-after$
 $endfor$
 </body>
 </html>
@@ -1,169 +0,0 @@
 ---
 // fetch all commits for just this page's path
 type Props = {
  path: string;
 };
 const { path } = Astro.props as Props;
 const resolvedPath = `website/src/pages${path}.mdx`;
 const url = `https://api.github.com/repos/tidalcycles/strudel/commits?path=${resolvedPath}`;
 const commitsURL = `https://github.com/tidalcycles/strudel/commits/main/${resolvedPath}`;
 type Commit = {
  author: {
    id: string;
    login: string;
  };
 };
 async function getCommits(url: string) {
  try {
    const token = import.meta.env.SNOWPACK_PUBLIC_GITHUB_TOKEN ?? 'hello';
    if (!token) {
      throw new Error('Cannot find "SNOWPACK_PUBLIC_GITHUB_TOKEN" used for escaping rate-limiting.');
    }
    const auth = `Basic ${Buffer.from(token, 'binary').toString('base64')}`;
    const res = await fetch(url, {
      method: 'GET',
      headers: {
        Authorization: auth,
        'User-Agent': 'astro-docs/1.0',
      },
    });
    const data = await res.json();
    if (!res.ok) {
      throw new Error(
        `Request to fetch commits failed. Reason: ${res.statusText}
       Message: ${data.message}`,
      );
    }
    return data as Commit[];
  } catch (e) {
    console.warn(`[error]  /src/components/AvatarList.astro 
    ${(e as any)?.message ?? e}`);
    return [] as Commit[];
  }
 }
 function removeDups(arr: Commit[]) {
  const map = new Map<string, Commit['author']>();
  for (let item of arr) {
    const author = item.author;
    // Deduplicate based on author.id
    //map.set(author.id, { login: author.login, id: author.id });
    author && map.set(author.id, { login: author.login, id: author.id });
  }
  return [...map.values()];
 }
 const data = await getCommits(url);
 const unique = removeDups(data);
 const recentContributors = unique.slice(0, 3); // only show avatars for the 3 most recent contributors
 const additionalContributors = unique.length - recentContributors.length; // list the rest of them as # of extra contributors
 ---
 <!-- Thanks to @5t3ph for https://smolcss.dev/#smol-avatar-list! -->
 <div class="contributors px-4 mb-8">
  <ul class="avatar-list" style={`--avatar-count: ${recentContributors.length}`}>
    {
      recentContributors.map((item) => (
        <li>
          <a href={`https://github.com/${item.login}`}>
            <img
              alt={`Contributor ${item.login}`}
              title={`Contributor ${item.login}`}
              width="64"
              height="64"
              src={`https://avatars.githubusercontent.com/u/${item.id}`}
            />
          </a>
        </li>
      ))
    }
  </ul>
  {
    additionalContributors > 0 && (
      <span>
        <a href={commitsURL}>{`and ${additionalContributors} additional contributor${
          additionalContributors > 1 ? 's' : ''
        }.`}</a>
      </span>
    )
  }
  {unique.length === 0 && <a href={commitsURL}>Contributors</a>}
 </div>
 <style>
  .avatar-list {
    --avatar-size: 2.5rem;
    --avatar-count: 3;
    display: grid;
    list-style: none;
    /* Default to displaying most of the avatar to
  enable easier access on touch devices, ensuring
  the WCAG touch target size is met or exceeded */
    grid-template-columns: repeat(var(--avatar-count), max(44px, calc(var(--avatar-size) / 1.15)));
    /* `padding` matches added visual dimensions of
  the `box-shadow` to help create a more accurate
  computed component size */
    padding: 0.08em;
    font-size: var(--avatar-size);
  }
  @media (any-hover: hover) and (any-pointer: fine) {
    .avatar-list {
      /* We create 1 extra cell to enable the computed 
    width to match the final visual width */
      grid-template-columns: repeat(calc(var(--avatar-count) + 1), calc(var(--avatar-size) / 1.75));
    }
  }
  .avatar-list li {
    width: var(--avatar-size);
    height: var(--avatar-size);
  }
  .avatar-list li:hover ~ li a,
  .avatar-list li:focus-within ~ li a {
    transform: translateX(33%);
  }
  .avatar-list img,
  .avatar-list a {
    display: block;
    border-radius: 50%;
  }
  .avatar-list a {
    transition: transform 180ms ease-in-out;
  }
  .avatar-list img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    background-color: #fff;
    box-shadow: 0 0 0 0.05em #fff, 0 0 0 0.08em rgba(0, 0, 0, 0.15);
  }
  .avatar-list a:focus {
    outline: 2px solid transparent;
    /* Double-layer trick to work for dark and light backgrounds */
    box-shadow: 0 0 0 0.08em var(--theme-accent), 0 0 0 0.12em white;
  }
  .contributors {
    display: flex;
    align-items: center;
  }
  .contributors > * + * {
    margin-left: 0.75rem;
  }
 </style>
@@ -82,7 +82,7 @@ export default function Search() {
            appId={ALGOLIA.appId}
            apiKey={ALGOLIA.apiKey}
            getMissingResultsUrl={({ query }) => {
-              return `https://github.com/tidalcycles/strudel/issues/new?title=Missing doc for ${query}`;
+              return `https://codeberg.org/uzu/strudel/issues/new?title=Missing%20doc%20for${encodeURIComponent(query)}`;
            }}
            transformItems={(items) => {
              return items.map((item) => {
@@ -18,5 +18,4 @@ currentPage = currentPage.endsWith('/') ? currentPage.slice(0, -1) : currentPage
 <nav aria-labelledby="grid-right" class="w-64 text-foreground">
  <TableOfContents client:media="(min-width: 50em)" headings={headings} currentPage={currentPage} />
  <MoreMenu editHref={githubEditUrl} />
  <!-- <AvatarList path={currentPage} /> -->
 </nav>
@@ -1,6 +1,6 @@
 /*
 cx.js - <short description TODO>
-Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/repl/src/cx.js>
+Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/repl/src/cx.js>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
@@ -14,7 +14,7 @@ These pages will introduce you to [Strudel](https://strudel.cc/), a web-based [l
 # What is Strudel?
-[Strudel](https://strudel.cc/) is a version of [Tidal Cycles](https://tidalcycles.org) written in [JavaScript](https://developer.mozilla.org/en-US/docs/Web/JavaScript), initiated by [Alex McLean](https://slab.org) and [Felix Roos](https://github.com/felixroos) in 2022.
+[Strudel](https://strudel.cc/) is a version of [Tidal Cycles](https://tidalcycles.org) written in [JavaScript](https://developer.mozilla.org/en-US/docs/Web/JavaScript), initiated by [Alex McLean](https://slab.org) and [Felix Roos](https://froos.cc/) in 2022.
 Tidal Cycles, also known as Tidal, is a language for [algorithmic pattern](https://algorithmicpattern.org), and though it is most commonly used for [making music](https://tidalcycles.org/docs/showcase), it can be used for any kind of pattern making activity, including [weaving](https://www.youtube.com/watch?v=TfEmEsusXjU).
 Tidal was first implemented as a library written in the [Haskell](https://www.haskell.org/) functional programming language, and by itself it does not make any sound.
@@ -1,6 +1,6 @@
 /*
 Repl.jsx - <short description TODO>
-Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/repl/src/App.js>
+Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/repl/src/App.js>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
@@ -70,7 +70,7 @@ export function Reference() {
              <ul>
                {entry.params?.map(({ name, type, description }, i) => (
                  <li key={i}>
-                    {name} : {type.names?.join(' | ')} {description ? <> - {getInnerText(description)}</> : ''}
+                    {name} : {type?.names?.join(' | ')} {description ? <> - {getInnerText(description)}</> : ''}
                  </li>
                ))}
              </ul>
@@ -38,11 +38,11 @@ export function WelcomeTab({ context }) {
        </a>
        , which is a popular live coding language for music, written in Haskell. Strudel is free/open source software:
        you can redistribute and/or modify it under the terms of the{' '}
-        <a href="https://github.com/tidalcycles/strudel/blob/main/LICENSE" target="_blank">
+        <a href="https://codeberg.org/uzu/strudel/src/branch/main/LICENSE" target="_blank">
          GNU Affero General Public License
        </a>
        . You can find the source code at{' '}
-        <a href="https://github.com/tidalcycles/strudel" target="_blank">
+        <a href="https://codeberg.org/uzu/strudel" target="_blank">
          github
        </a>
        . You can also find <a href="https://github.com/felixroos/dough-samples/blob/main/README.md">licensing info</a>{' '}
@@ -1,6 +1,6 @@
 /*
 tunes.mjs - <short description TODO>
-Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/repl/src/tunes.mjs>
+Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/repl/src/tunes.mjs>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
@@ -1,6 +1,6 @@
 /*
 Repl.jsx - <short description TODO>
-Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/repl/src/App.js>
+Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/repl/src/App.js>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
Author	SHA1	Message	Date
Jade (Rose) Rowland	7e6876c282	comment	2025-06-18 20:44:09 -04:00
Jade (Rose) Rowland	011139eff8	arch2	2025-06-18 20:12:36 +02:00
Jade (Rose) Rowland	184cb746f3	arch	2025-06-18 19:55:30 +02:00
alex	351314ccdf	rename .github to .forgejo	2025-06-15 09:23:29 +01:00
Felix Roos	e52017c0d8	fix: reference tab critical fail	2025-06-15 10:12:17 +02:00
alex	b253d437d3	Merge branch 'main' of ssh://codeberg.org/uzu/strudel	2025-06-15 08:06:12 +01:00
alex	bebbe30b50	codeformat	2025-06-15 08:03:23 +01:00
alex	489d3f8d4d	Merge branch 'reorganise-docs'	2025-06-15 08:01:44 +01:00
alex	cc4cad05b2	add the technical manual again	2025-06-14 23:33:52 +01:00
alex	2cb22e94b5	move iclc paper under docs/	2025-06-14 23:26:59 +01:00
Felix Roos	ee7d783099	fix homepage link	2025-06-14 16:27:54 +02:00
Felix Roos	9becd0a3f0	Merge branch 'main' of https://codeberg.org/uzu/strudel	2025-06-14 16:23:36 +02:00
Felix Roos	9738c90b82	even more degithubbing	2025-06-14 16:23:03 +02:00
Alex McLean	f7b58f2e3e	Merge pull request 'link back to tech manual in wiki' (#1382 ) from techmanual-wiki into main Reviewed-on: https://codeberg.org/uzu/strudel/pulls/1382	2025-06-14 16:22:59 +02:00
alex	d856e567c1	link back to tech manual in wiki	2025-06-14 15:22:27 +01:00
Felix Roos	a7f044e1aa	more degithubbing	2025-06-14 16:17:22 +02:00
froos	1f7d78c6ce	Merge pull request 'degithub-links' (#1380 ) from degithub-links into main Reviewed-on: https://codeberg.org/uzu/strudel/pulls/1380	2025-06-14 14:55:36 +02:00
`@@ -2,4 +2,4 @@`

	`Each folder represents one of the @strudel/* packages [published to npm](https://www.npmjs.com/org/strudel).`	`Each folder represents one of the @strudel/* packages [published to npm](https://www.npmjs.com/org/strudel).`

	`To understand how those pieces connect, refer to the [Technical Manual](https://codeberg.org/uzu/strudel/src/branch/main/technical-manual.md) or the individual READMEs.`	`To understand how those pieces connect, refer to the [Technical Manual](https://codeberg.org/uzu/strudel/wiki/Technical-Manual) or the individual READMEs.`