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diff --git a/carboxyl/index.html b/carboxyl/index.html new file mode 100644 index 0000000..345e4c3 --- /dev/null +++ b/carboxyl/index.html @@ -0,0 +1,272 @@ +<!DOCTYPE html> +<html lang="en"> +<head> + <meta charset="utf-8"> + <meta name="viewport" content="width=device-width, initial-scale=1.0"> + <meta name="generator" content="rustdoc"> + <meta name="description" content="API documentation for the Rust `carboxyl` crate."> + <meta name="keywords" content="rust, rustlang, rust-lang, carboxyl"> + + <title>carboxyl - Rust</title> + + <link rel="stylesheet" type="text/css" href="../main.css"> + + + +</head> +<body class="rustdoc"> + <!--[if lte IE 8]> + <div class="warning"> + This old browser is unsupported and will most likely display funky + things. + </div> + <![endif]--> + + + + <section class="sidebar"> + + <p class='location'></p><script>window.sidebarCurrent = {name: 'carboxyl', ty: 'mod', relpath: '../'};</script> + </section> + + <nav class="sub"> + <form class="search-form js-only"> + <div class="search-container"> + <input class="search-input" name="search" + autocomplete="off" + placeholder="Click or press 'S' to search, '?' for more options..." + type="search"> + </div> + </form> + </nav> + + <section id='main' class="content mod"> +<h1 class='fqn'><span class='in-band'>Crate <a class='mod' href=''>carboxyl</a></span><span class='out-of-band'><span id='render-detail'> + <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs"> + [<span class='inner'>−</span>] + </a> + </span><a id='src-0' class='srclink' href='../src/carboxyl/lib.rs.html#1-161' title='goto source code'>[src]</a></span></h1> +<div class='docblock'><p><em>Carboxyl</em> provides primitives for functional reactive programming in Rust. +It draws inspiration from the <a href="https://github.com/SodiumFRP/sodium/">Sodium</a> libraries and Push-Pull FRP, +as described by <a href="http://conal.net/papers/push-pull-frp/push-pull-frp.pdf">Elliott (2009)</a>.</p> + +<h1 id="overview" class='section-header'><a + href="#overview">Overview</a></h1> +<p>Functional reactive programming (FRP) is a composable and modular +abstraction for creating dynamic and reactive systems. In its most general +form it models these systems as a composition of two basic primitives: +<em>streams</em> are a series of singular events and <em>signals</em> are continuously +changing values.</p> + +<p><em>Carboxyl</em> is an imperative, hybrid push- and pull-based implementation of +FRP. Streams and the discrete components of signals are data-driven, i.e. +whenever an event occurs the resulting changes are propagated to everything +that depends on it.</p> + +<p>However, the continuous components of signals are demand-driven. Internally, +<em>Carboxyl</em> stores the state of a signal as a function. This function has to +be evaluated by consumers of a signal to obtain a concrete value.</p> + +<p>Nonetheless, <em>Carboxyl</em> has no explicit notion of time. Its signals are +functions that can be evaluated at any time, but they do not carry any +inherent notion of time. Synchronization and atomicity is achieved by a +transaction system.</p> + +<h1 id="functional-reactive-primitives" class='section-header'><a + href="#functional-reactive-primitives">Functional reactive primitives</a></h1> +<p>This library provides two basic types: <code>Stream</code> and <code>Signal</code>. A stream is a +discrete sequence of events, a signal is a container for values that change +(discretely) over time.</p> + +<p>The FRP primitives are mostly implemented as methods of the basic types to +ease method chaining, except for the various lifting functions, as they do +not really belong to any type in particular.</p> + +<p>In addition, the <code>Sink</code> type allows one to create a stream of events by +sending values into it. It is the only way to create a stream from scratch, +i.e. without using any of the other primitives.</p> + +<h1 id="usage-example" class='section-header'><a + href="#usage-example">Usage example</a></h1> +<p>Here is a simple example of how you can use the primitives provided by +<em>Carboxyl</em>. First of all, events can be sent into a <em>sink</em>. From a sink one +can create a <em>stream</em> of events. Streams can also be filtered, mapped and +merged. One can e.g. hold the last event from a stream as a signal.</p> +<pre class='rust rust-example-rendered'> +<span class='kw'>use</span> <span class='ident'>carboxyl</span>::<span class='ident'>Sink</span>; + +<span class='kw'>let</span> <span class='ident'>sink</span> <span class='op'>=</span> <span class='ident'>Sink</span>::<span class='ident'>new</span>(); +<span class='kw'>let</span> <span class='ident'>stream</span> <span class='op'>=</span> <span class='ident'>sink</span>.<span class='ident'>stream</span>(); +<span class='kw'>let</span> <span class='ident'>signal</span> <span class='op'>=</span> <span class='ident'>stream</span>.<span class='ident'>hold</span>(<span class='number'>3</span>); + +<span class='comment'>// The current value of the signal is initially 3</span> +<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>signal</span>.<span class='ident'>sample</span>(), <span class='number'>3</span>); + +<span class='comment'>// When we fire an event, the signal get updated accordingly</span> +<span class='ident'>sink</span>.<span class='ident'>send</span>(<span class='number'>5</span>); +<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>signal</span>.<span class='ident'>sample</span>(), <span class='number'>5</span>); +</pre> + +<p>One can also directly iterate over the stream instead of holding it in a +signal:</p> +<pre class='rust rust-example-rendered'> +<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>events</span> <span class='op'>=</span> <span class='ident'>stream</span>.<span class='ident'>events</span>(); +<span class='ident'>sink</span>.<span class='ident'>send</span>(<span class='number'>4</span>); +<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>events</span>.<span class='ident'>next</span>(), <span class='prelude-val'>Some</span>(<span class='number'>4</span>)); +</pre> + +<p>Streams and signals can be combined using various primitives. We can map a +stream to another stream using a function:</p> +<pre class='rust rust-example-rendered'> +<span class='kw'>let</span> <span class='ident'>squares</span> <span class='op'>=</span> <span class='ident'>stream</span>.<span class='ident'>map</span>(<span class='op'>|</span><span class='ident'>x</span><span class='op'>|</span> <span class='ident'>x</span> <span class='op'>*</span> <span class='ident'>x</span>).<span class='ident'>hold</span>(<span class='number'>0</span>); +<span class='ident'>sink</span>.<span class='ident'>send</span>(<span class='number'>4</span>); +<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>squares</span>.<span class='ident'>sample</span>(), <span class='number'>16</span>); +</pre> + +<p>Or we can filter a stream to create a new one that only contains events that +satisfy a certain predicate:</p> +<pre class='rust rust-example-rendered'> +<span class='kw'>let</span> <span class='ident'>negatives</span> <span class='op'>=</span> <span class='ident'>stream</span>.<span class='ident'>filter</span>(<span class='op'>|</span><span class='kw-2'>&</span><span class='ident'>x</span><span class='op'>|</span> <span class='ident'>x</span> <span class='op'><</span> <span class='number'>0</span>).<span class='ident'>hold</span>(<span class='number'>0</span>); + +<span class='comment'>// This won't arrive at the signal.</span> +<span class='ident'>sink</span>.<span class='ident'>send</span>(<span class='number'>4</span>); +<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>negatives</span>.<span class='ident'>sample</span>(), <span class='number'>0</span>); + +<span class='comment'>// But this will!</span> +<span class='ident'>sink</span>.<span class='ident'>send</span>(<span class='op'>-</span><span class='number'>3</span>); +<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>negatives</span>.<span class='ident'>sample</span>(), <span class='op'>-</span><span class='number'>3</span>); +</pre> + +<p>There are some other methods on streams and signals, that you can find in +their respective APIs.</p> + +<p>Note that all these objects are <code>Send + Sync + Clone</code>. This means you can +easily pass them around in your code, make clones, give them to another +thread, and they will still be updated correctly.</p> + +<p>You may have noticed that certain primitives take a function as an argument. +There is a limitation on what kind of functions can and should be used here. +In general, as FRP provides an abstraction around mutable state, they should +be pure functions (i.e. free of side effects).</p> + +<p>For the most part this is guaranteed by Rust's type system. A static +function with a matching signature always works. A closure though is very +restricted: it must not borrow its environment, as it is impossible to +satisfy the lifetime requirements for that. So you can only move stuff into +it from the environment. However, the moved contents of the closure may also +not be altered, which is guaranteed by the <code>Fn(…) -> …)</code> trait bound.</p> + +<p>However, both closures and functions could still have side effects such as +I/O, changing mutable state via <code>Mutex</code> or <code>RefCell</code>, etc. While Rust's type +system cannot prevent this, you should generally not pass such functions to +the FRP primitives, as they break the benefits you get from using FRP. +(An exception here is debugging output.)</p> +</div><h2 id='modules' class='section-header'><a href="#modules">Modules</a></h2> +<table> + <tr class=' module-item'> + <td><a class='mod' href='lift/index.html' + title='carboxyl::lift'>lift</a></td> + <td class='docblock short'> + <p>Lifting of n-ary functions.</p> + + </td> + </tr> + </table><h2 id='macros' class='section-header'><a href="#macros">Macros</a></h2> +<table> + <tr class=' module-item'> + <td><a class='macro' href='macro.lift!.html' + title='carboxyl::lift!'>lift!</a></td> + <td class='docblock short'> + + </td> + </tr> + </table><h2 id='structs' class='section-header'><a href="#structs">Structs</a></h2> +<table> + <tr class=' module-item'> + <td><a class='struct' href='struct.Signal.html' + title='carboxyl::Signal'>Signal</a></td> + <td class='docblock short'> + <p>A continuous signal that changes over time.</p> + + </td> + </tr> + + <tr class=' module-item'> + <td><a class='struct' href='struct.SignalMut.html' + title='carboxyl::SignalMut'>SignalMut</a></td> + <td class='docblock short'> + <p>Signal variant using inner mutability for efficient in-place updates.</p> + + </td> + </tr> + + <tr class=' module-item'> + <td><a class='struct' href='struct.Sink.html' + title='carboxyl::Sink'>Sink</a></td> + <td class='docblock short'> + <p>An event sink.</p> + + </td> + </tr> + + <tr class=' module-item'> + <td><a class='struct' href='struct.Stream.html' + title='carboxyl::Stream'>Stream</a></td> + <td class='docblock short'> + <p>A stream of events.</p> + + </td> + </tr> + </table></section> + <section id='search' class="content hidden"></section> + + <section class="footer"></section> + + <div id="help" class="hidden"> + <div class="shortcuts"> + <h1>Keyboard shortcuts</h1> + <dl> + <dt>?</dt> + <dd>Show this help dialog</dd> + <dt>S</dt> + <dd>Focus the search field</dd> + <dt>⇤</dt> + <dd>Move up in search results</dd> + <dt>⇥</dt> + <dd>Move down in search results</dd> + <dt>⏎</dt> + <dd>Go to active search result</dd> + </dl> + </div> + <div class="infos"> + <h1>Search tricks</h1> + <p> + Prefix searches with a type followed by a colon (e.g. + <code>fn:</code>) to restrict the search to a given type. + </p> + <p> + Accepted types are: <code>fn</code>, <code>mod</code>, + <code>struct</code>, <code>enum</code>, + <code>trait</code>, <code>typedef</code> (or + <code>tdef</code>). + </p> + <p> + Search functions by type signature (e.g. + <code>vec -> usize</code>) + </p> + </div> + </div> + + + + <script> + window.rootPath = "../"; + window.currentCrate = "carboxyl"; + window.playgroundUrl = ""; + </script> + <script src="../jquery.js"></script> + <script src="../main.js"></script> + + <script async src="../search-index.js"></script> +</body> +</html>
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