<!DOCTYPE html><htmllang="en"><head><metacharset="utf-8"><metaname="viewport"content="width=device-width, initial-scale=1.0"><metaname="generator"content="rustdoc"><metaname="description"content="Trait for types the `Lexer` can read from."><title>Source in logos::source - Rust</title><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../static.files/SourceSerif4-Regular-46f98efaafac5295.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../static.files/FiraSans-Regular-018c141bf0843ffd.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../static.files/FiraSans-Medium-8f9a781e4970d388.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../static.files/SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../static.files/SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2"><linkrel="stylesheet"href="../../static.files/normalize-76eba96aa4d2e634.css"><linkrel="stylesheet"href="../../static.files/rustdoc-5bc39a1768837dd0.css"><metaname="rustdoc-vars"data-root-path="../../"data-static-root-path="../../static.files/"data-current-crate="logos"data-themes=""data-resource-suffix=""data-rustdoc-version="1.77.1 (7cf61ebde 2024-03-27)"data-channel="1.77.1"data-search-js="search-dd67cee4cfa65049.js"data-settings-js="settings-4313503d2e1961c2.js"><scriptsrc="../../static.files/storage-4c98445ec4002617.js"></script><scriptdefersrc="sidebar-items.js"></script><scriptdefersrc="../../static.files/main-48f368f3872407c8.js"></script><noscript><linkrel="stylesheet"href="../../static.files/noscript-04d5337699b92874.css"></noscript><linkrel="alternate icon"type="image/png"href="../../static.files/favicon-16x16-8b506e7a72182f1c.png"><linkrel="alternate icon"type="image/png"href="../../static.files/favicon-32x32-422f7d1d52889060.png"><linkrel="icon"type="image/svg+xml"href="../../static.files/favicon-2c020d218678b618.svg"></head><bodyclass="rustdoc trait"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><navclass="mobile-topbar"><buttonclass="sidebar-menu-toggle"title="show sidebar"></button><aclass="logo-container"href="../../logos/index.html"><imgsrc="https://maciej.codes/kosz/logos.png"alt=""></a></nav><navclass="sidebar"><divclass="sidebar-crate"><aclass="logo-container"href="../../logos/index.html"><imgsrc="https://maciej.codes/kosz/logos.png"alt="logo"></a><h2><ahref="../../logos/index.html">logos</a><spanclass="version">0.14.0</span></h2></div><h2class="location"><ahref="#">Source</a></h2><divclass="sidebar-elems"><section><h3><ahref="#required-associated-types">Required Associated Types</a></h3><ulclass="block"><li><ahref="#associatedtype.Slice">Slice</a></li></ul><h3><ahref="#required-methods">Required Methods</a></h3><ulclass="block"><li><ahref="#tymethod.is_boundary">is_boundary</a></li><li><ahref="#tymethod.len">len</a></li><li><ahref="#tymethod.read">read</a></li><li><ahref="#tymethod.read_unchecked">read_unchecked</a></li><li><ahref="#tymethod.slice">slice</a></li><li><ahref="#tymethod.slice_unchecked">slice_unchecked</a></li></ul><h3><ahref="#provided-methods">Provided Methods</a></h3><ulclass="block"><li><ahref="#method.find_boundary">find_boundary</a></li></ul><h3><ahref="#foreign-impls">Implementations on Foreign Types</a></h3><ulclass="block"><li><ahref="#impl-Source-for-%5Bu8%5D">[u8]</a></li><li><ahref="#impl-Source-for-str">str</a></li></ul><h3><ahref="#object-safety">Object Safety</a></h3><h3><ahref="#implementors">Implementors</a></h3></section><h2><ahref="index.html">In logos::source</a></h2></div></nav><divclass="sidebar-resizer"></div>
<main><divclass="width-limiter"><navclass="sub"><formclass="search-form"><span></span><divid="sidebar-button"tabindex="-1"><ahref="../../logos/all.html"title="show sidebar"></a></div><inputclass="search-input"name="search"aria-label="Run search in the documentation"autocomplete="off"spellcheck="false"placeholder="Click or press ‘S’ to search, ‘?’ for more options…"type="search"><divid="help-button"tabindex="-1"><ahref="../../help.html"title="help">?</a></div><divid="settings-menu"tabindex="-1"><ahref="../../settings.html"title="settings"><imgwidth="22"height="22"alt="Change settings"src="../../static.files/wheel-7b819b6101059cd0.svg"></a></div></form></nav><sectionid="main-content"class="content"><divclass="main-heading"><h1>Trait <ahref="../index.html">logos</a>::<wbr><ahref="index.html">source</a>::<wbr><aclass="trait"href="#">Source</a><buttonid="copy-path"title="Copy item path to clipboard"><imgsrc="../../static.files/clipboard-7571035ce49a181d.svg"width="19"height="18"alt="Copy item path"></button></h1><spanclass="out-of-band"><aclass="src"href="../../src/logos/source.rs.html#16-98">source</a> · <buttonid="toggle-all-docs"title="collapse all docs">[<span>−</span>]</button></span></div><preclass="rust item-decl"><code>pub trait Source {
}</code></pre><detailsclass="toggle top-doc"open><summaryclass="hideme"><span>Expand description</span></summary><divclass="docblock"><p>Trait for types the <code>Lexer</code> can read from.</p>
<p>Most notably this is implemented for <code>&str</code>. It is unlikely you will
ever want to use this Trait yourself, unless implementing a new <code>Source</code>
</div></details></div><h2id="required-methods"class="section-header">Required Methods<ahref="#required-methods"class="anchor">§</a></h2><divclass="methods"><detailsclass="toggle method-toggle"open><summary><sectionid="tymethod.len"class="method"><aclass="src rightside"href="../../src/logos/source.rs.html#23">source</a><h4class="code-header">fn <ahref="#tymethod.len"class="fn">len</a>(&self) -><aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.usize.html">usize</a></h4></section></summary><divclass="docblock"><p>Length of the source</p>
Chunk: <aclass="trait"href="trait.Chunk.html"title="trait logos::source::Chunk">Chunk</a><'a>,</div></h4></section></summary><divclass="docblock"><p>Read a chunk of bytes into an array. Returns <code>None</code> when reading
out of bounds would occur.</p>
<p>This is very useful for matching fixed-size byte arrays, and tends
to be very fast at it too, since the compiler knows the byte lengths.</p>
</span><spanclass="macro">assert_eq!</span>(foo.read::<<spanclass="kw-2">&</span>[u8; <spanclass="number">4</span>]>(<spanclass="number">0</span>), <spanclass="prelude-val">None</span>); <spanclass="comment">// Out of bounds
</span><spanclass="macro">assert_eq!</span>(foo.read::<<spanclass="kw-2">&</span>[u8; <spanclass="number">2</span>]>(<spanclass="number">2</span>), <spanclass="prelude-val">None</span>); <spanclass="comment">// Out of bounds</span></code></pre></div>
Chunk: <aclass="trait"href="trait.Chunk.html"title="trait logos::source::Chunk">Chunk</a><'a>,</div></h4></section></summary><divclass="docblock"><p>Read a chunk of bytes into an array without doing bounds checks.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="tymethod.slice"class="method"><aclass="src rightside"href="../../src/logos/source.rs.html#64">source</a><h4class="code-header">fn <ahref="#tymethod.slice"class="fn">slice</a>(&self, range: <aclass="struct"href="https://doc.rust-lang.org/1.77.1/core/ops/range/struct.Range.html"title="struct core::ops::range::Range">Range</a><<aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.usize.html">usize</a>>) -><aclass="enum"href="https://doc.rust-lang.org/1.77.1/core/option/enum.Option.html"title="enum core::option::Option">Option</a><Self::<aclass="associatedtype"href="trait.Source.html#associatedtype.Slice"title="type logos::source::Source::Slice">Slice</a><'_>></h4></section></summary><divclass="docblock"><p>Get a slice of the source at given range. This is analogous to
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="tymethod.slice_unchecked"class="method"><aclass="src rightside"href="../../src/logos/source.rs.html#82">source</a><h4class="code-header">unsafe fn <ahref="#tymethod.slice_unchecked"class="fn">slice_unchecked</a>(&self, range: <aclass="struct"href="https://doc.rust-lang.org/1.77.1/core/ops/range/struct.Range.html"title="struct core::ops::range::Range">Range</a><<aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.usize.html">usize</a>>) -> Self::<aclass="associatedtype"href="trait.Source.html#associatedtype.Slice"title="type logos::source::Source::Slice">Slice</a><'_></h4></section></summary><divclass="docblock"><p>Get a slice of the source at given range. This is analogous to
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="tymethod.is_boundary"class="method"><aclass="src rightside"href="../../src/logos/source.rs.html#97">source</a><h4class="code-header">fn <ahref="#tymethod.is_boundary"class="fn">is_boundary</a>(&self, index: <aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.usize.html">usize</a>) -><aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.bool.html">bool</a></h4></section></summary><divclass="docblock"><p>Check if <code>index</code> is valid for this <code>Source</code>, that is:</p>
</div></details></div><h2id="provided-methods"class="section-header">Provided Methods<ahref="#provided-methods"class="anchor">§</a></h2><divclass="methods"><detailsclass="toggle method-toggle"open><summary><sectionid="method.find_boundary"class="method"><aclass="src rightside"href="../../src/logos/source.rs.html#89-91">source</a><h4class="code-header">fn <ahref="#method.find_boundary"class="fn">find_boundary</a>(&self, index: <aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.usize.html">usize</a>) -><aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.usize.html">usize</a></h4></section></summary><divclass="docblock"><p>For <code>&str</code> sources attempts to find the closest <code>char</code> boundary at which source
