<!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="A layout strategy within a circuit. The layouter is chip-agnostic and applies its strategy to the context and config it is given."><metaname="keywords"content="rust, rustlang, rust-lang, Layouter"><title>Layouter in halo2_proofs::circuit - Rust</title><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../SourceSerif4-Regular.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../FiraSans-Regular.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../FiraSans-Medium.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../SourceCodePro-Regular.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../SourceSerif4-Bold.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../SourceCodePro-Semibold.ttf.woff2"><linkrel="stylesheet"type="text/css"href="../../normalize.css"><linkrel="stylesheet"type="text/css"href="../../rustdoc.css"id="mainThemeStyle"><linkrel="stylesheet"type="text/css"href="../../ayu.css"disabled><linkrel="stylesheet"type="text/css"href="../../dark.css"disabled><linkrel="stylesheet"type="text/css"href="../../light.css"id="themeStyle"><scriptid="default-settings"></script><scriptsrc="../../storage.js"></script><scriptsrc="../../crates.js"></script><scriptdefersrc="../../main.js"></script>
</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">☰</button><aclass="sidebar-logo"href="../../halo2_proofs/index.html"><divclass="logo-container"><imgclass="rust-logo"src="../../rust-logo.svg"alt="logo"></div>
</a><h2class="location"><ahref="#">Layouter</a></h2><divclass="sidebar-elems"><section><divclass="block"><h3class="sidebar-title"><ahref="#required-associated-types">Required Associated Types</a></h3><ul><li><ahref="#associatedtype.Root">Root</a></li></ul></div><divclass="block"><h3class="sidebar-title"><ahref="#required-methods">Required Methods</a></h3><ul><li><ahref="#tymethod.assign_region">assign_region</a></li><li><ahref="#tymethod.assign_table">assign_table</a></li><li><ahref="#tymethod.constrain_instance">constrain_instance</a></li><li><ahref="#tymethod.get_root">get_root</a></li><li><ahref="#tymethod.pop_namespace">pop_namespace</a></li><li><ahref="#tymethod.push_namespace">push_namespace</a></li></ul></div><divclass="block"><h3class="sidebar-title"><ahref="#provided-methods">Provided Methods</a></h3><ul><li><ahref="#method.namespace">namespace</a></li></ul></div><divclass="block"><h3class="sidebar-title"><ahref="#implementors">Implementors</a></h3></div></section><h2class="location"><ahref="index.html">In halo2_proofs::circuit</a></h2><divid="sidebar-vars"data-name="Layouter"data-ty="trait"data-relpath=""></div><scriptdefersrc="sidebar-items.js"></script></div></nav><main><divclass="width-limiter"><divclass="sub-container"><aclass="sub-logo-container"href="../../halo2_proofs/index.html"><imgclass="rust-logo"src="../../rust-logo.svg"alt="logo"></a><navclass="sub"><formclass="search-form"><divclass="search-container"><span></span><inputclass="search-input"name="search"autocomplete="off"spellcheck="false"placeholder="Click or press ‘S’ to search, ‘?’ for more options…"type="search"><buttontype="button"id="help-button"title="help">?</button><divid="settings-menu"tabindex="-1">
type <ahref="#associatedtype.Root"class="associatedtype">Root</a>: <aclass="trait"href="trait.Layouter.html"title="trait halo2_proofs::circuit::Layouter">Layouter</a><F>;
}</code></pre></div><detailsclass="rustdoc-toggle top-doc"open><summaryclass="hideme"><span>Expand description</span></summary><divclass="docblock"><p>A layout strategy within a circuit. The layouter is chip-agnostic and applies its
strategy to the context and config it is given.</p>
<p>This abstracts over the circuit assignments, handling row indices etc.</p>
</div></details><h2id="required-associated-types"class="small-section-header">Required Associated Types<ahref="#required-associated-types"class="anchor"></a></h2><divclass="methods"><detailsclass="rustdoc-toggle"open><summary><divid="associatedtype.Root"class="method has-srclink"><divclass="rightside"><aclass="srclink"href="../../src/halo2_proofs/circuit.rs.html#399">source</a></div><h4class="code-header">type <ahref="#associatedtype.Root"class="associatedtype">Root</a>: <aclass="trait"href="trait.Layouter.html"title="trait halo2_proofs::circuit::Layouter">Layouter</a><F></h4></div></summary><divclass="docblock"><p>Represents the type of the “root” of this layouter, so that nested namespaces
</div></details><detailsclass="rustdoc-toggle"open><summary><divid="tymethod.constrain_instance"class="method has-srclink"><divclass="rightside"><aclass="srclink"href="../../src/halo2_proofs/circuit.rs.html#435-440">source</a></div><h4class="code-header">fn <ahref="#tymethod.constrain_instance"class="fnname">constrain_instance</a>(<br> &mut self, <br> cell: <aclass="struct"href="struct.Cell.html"title="struct halo2_proofs::circuit::Cell">Cell</a>, <br> column: <aclass="struct"href="../plonk/struct.Column.html"title="struct halo2_proofs::plonk::Column">Column</a><<aclass="struct"href="../plonk/struct.Instance.html"title="struct halo2_proofs::plonk::Instance">Instance</a>>, <br> row: <aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.usize.html">usize</a><br>) -><aclass="enum"href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html"title="enum core::result::Result">Result</a><<aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>, <aclass="enum"href="../plonk/enum.Error.html"title="enum halo2_proofs::plonk::Error">Error</a>></h4></div></summary><divclass="docblock"><p>Constrains a <ahref="struct.Cell.html"title="Cell"><code>Cell</code></a> to equal an instance column’s row value at an
</div></details><detailsclass="rustdoc-toggle"open><summary><divid="tymethod.get_root"class="method has-srclink"><divclass="rightside"><aclass="srclink"href="../../src/halo2_proofs/circuit.rs.html#445">source</a></div><h4class="code-header">fn <ahref="#tymethod.get_root"class="fnname">get_root</a>(&mut self) ->&mut Self::<aclass="associatedtype"href="trait.Layouter.html#associatedtype.Root"title="type halo2_proofs::circuit::Layouter::Root">Root</a></h4></div></summary><divclass="docblock"><p>Gets the “root” of this assignment, bypassing the namespacing.</p>
<p>Not intended for downstream consumption; use <ahref="trait.Layouter.html#method.namespace"title="Layouter::namespace"><code>Layouter::namespace</code></a> instead.</p>
<p>Not intended for downstream consumption; use <ahref="trait.Layouter.html#method.namespace"title="Layouter::namespace"><code>Layouter::namespace</code></a> instead.</p>
</div></details><detailsclass="rustdoc-toggle"open><summary><divid="tymethod.pop_namespace"class="method has-srclink"><divclass="rightside"><aclass="srclink"href="../../src/halo2_proofs/circuit.rs.html#458">source</a></div><h4class="code-header">fn <ahref="#tymethod.pop_namespace"class="fnname">pop_namespace</a>(&mut self, gadget_name: <aclass="enum"href="https://doc.rust-lang.org/nightly/core/option/enum.Option.html"title="enum core::option::Option">Option</a><<aclass="struct"href="https://doc.rust-lang.org/nightly/alloc/string/struct.String.html"title="struct alloc::string::String">String</a>>)</h4></div></summary><divclass="docblock"><p>Exits out of the existing namespace.</p>
<p>Not intended for downstream consumption; use <ahref="trait.Layouter.html#method.namespace"title="Layouter::namespace"><code>Layouter::namespace</code></a> instead.</p>
