<!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="This trait allows a [`Circuit`] to direct some backend to assign a witness for a constraint system."><metaname="keywords"content="rust, rustlang, rust-lang, Assignment"><title>Assignment in halo2_proofs::plonk - 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>
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</a><h2class="location"><ahref="#">Assignment</a></h2><divclass="sidebar-elems"><section><divclass="block"><h3class="sidebar-title"><ahref="#required-methods">Required Methods</a></h3><ul><li><ahref="#tymethod.assign_advice">assign_advice</a></li><li><ahref="#tymethod.assign_fixed">assign_fixed</a></li><li><ahref="#tymethod.copy">copy</a></li><li><ahref="#tymethod.enable_selector">enable_selector</a></li><li><ahref="#tymethod.enter_region">enter_region</a></li><li><ahref="#tymethod.exit_region">exit_region</a></li><li><ahref="#tymethod.fill_from_row">fill_from_row</a></li><li><ahref="#tymethod.pop_namespace">pop_namespace</a></li><li><ahref="#tymethod.push_namespace">push_namespace</a></li><li><ahref="#tymethod.query_instance">query_instance</a></li></ul></div><divclass="block"><h3class="sidebar-title"><ahref="#implementors">Implementors</a></h3></div></section><h2class="location"><ahref="index.html">In halo2_proofs::plonk</a></h2><divid="sidebar-vars"data-name="Assignment"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">
}</code></pre></div><detailsclass="rustdoc-toggle top-doc"open><summaryclass="hideme"><span>Expand description</span></summary><divclass="docblock"><p>This trait allows a <ahref="trait.Circuit.html"title="Circuit"><code>Circuit</code></a> to direct some backend to assign a witness
</div></details><h2id="required-methods"class="small-section-header">Required Methods<ahref="#required-methods"class="anchor"></a></h2><divclass="methods"><detailsclass="rustdoc-toggle"open><summary><divid="tymethod.enter_region"class="method has-srclink"><divclass="rightside"><aclass="srclink"href="../../src/halo2_proofs/plonk/circuit.rs.html#304-307">source</a></div><h4class="code-header">fn <ahref="#tymethod.enter_region"class="fnname">enter_region</a><NR, N>(&mut self, name_fn: N) <spanclass="where fmt-newline">where<br> NR: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.Into.html"title="trait core::convert::Into">Into</a><<aclass="struct"href="https://doc.rust-lang.org/nightly/alloc/string/struct.String.html"title="struct alloc::string::String">String</a>>,<br> N: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/ops/function/trait.FnOnce.html"title="trait core::ops::function::FnOnce">FnOnce</a>() -> NR, </span></h4></div></summary><divclass="docblock"><p>Creates a new region and enters into it.</p>
<p>Panics if we are currently in a region (if <code>exit_region</code> was not called).</p>
<p>Not intended for downstream consumption; use <ahref="../circuit/trait.Layouter.html#method.assign_region"><code>Layouter::assign_region</code></a> instead.</p>
</div></details><detailsclass="rustdoc-toggle"open><summary><divid="tymethod.exit_region"class="method has-srclink"><divclass="rightside"><aclass="srclink"href="../../src/halo2_proofs/plonk/circuit.rs.html#316">source</a></div><h4class="code-header">fn <ahref="#tymethod.exit_region"class="fnname">exit_region</a>(&mut self)</h4></div></summary><divclass="docblock"><p>Exits the current region.</p>
<p>Panics if we are not currently in a region (if <code>enter_region</code> was not called).</p>
<p>Not intended for downstream consumption; use <ahref="../circuit/trait.Layouter.html#method.assign_region"><code>Layouter::assign_region</code></a> instead.</p>
</div></details><detailsclass="rustdoc-toggle"open><summary><divid="tymethod.enable_selector"class="method has-srclink"><divclass="rightside"><aclass="srclink"href="../../src/halo2_proofs/plonk/circuit.rs.html#319-327">source</a></div><h4class="code-header">fn <ahref="#tymethod.enable_selector"class="fnname">enable_selector</a><A, AR>(<br> &mut self, <br> annotation: A, <br> selector: &<aclass="struct"href="struct.Selector.html"title="struct halo2_proofs::plonk::Selector">Selector</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="enum.Error.html"title="enum halo2_proofs::plonk::Error">Error</a>><spanclass="where fmt-newline">where<br> A: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/ops/function/trait.FnOnce.html"title="trait core::ops::function::FnOnce">FnOnce</a>() -> AR,<br> AR: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.Into.html"title="trait core::convert::Into">Into</a><<aclass="struct"href="https://doc.rust-lang.org/nightly/alloc/string/struct.String.html"title="struct alloc::string::String">String</a>>, </span></h4></div></summary><divclass="docblock"><p>Enables a selector at the given row.</p>
</div></details><detailsclass="rustdoc-toggle"open><summary><divid="tymethod.query_instance"class="method has-srclink"><divclass="rightside"><aclass="srclink"href="../../src/halo2_proofs/plonk/circuit.rs.html#332">source</a></div><h4class="code-header">fn <ahref="#tymethod.query_instance"class="fnname">query_instance</a>(<br> &self, <br> column: <aclass="struct"href="struct.Column.html"title="struct halo2_proofs::plonk::Column">Column</a><<aclass="struct"href="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="enum"href="https://doc.rust-lang.org/nightly/core/option/enum.Option.html"title="enum core::option::Option">Option</a><F>, <aclass="enum"href="enum.Error.html"title="enum halo2_proofs::plonk::Error">Error</a>></h4></div></summary><divclass="docblock"><p>Queries the cell of an instance column at a particular absolute row.</p>
</div></details><detailsclass="rustdoc-toggle"open><summary><divid="tymethod.copy"class="method has-srclink"><divclass="rightside"><aclass="srclink"href="../../src/halo2_proofs/plonk/circuit.rs.html#363-369">source</a></div><h4class="code-header">fn <ahref="#tymethod.copy"class="fnname">copy</a>(<br> &mut self, <br> left_column: <aclass="struct"href="struct.Column.html"title="struct halo2_proofs::plonk::Column">Column</a><<aclass="enum"href="enum.Any.html"title="enum halo2_proofs::plonk::Any">Any</a>>, <br> left_row: <aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.usize.html">usize</a>, <br> right_column: <aclass="struct"href="struct.Column.html"title="struct halo2_proofs::plonk::Column">Column</a><<aclass="enum"href="enum.Any.html"title="enum halo2_proofs::plonk::Any">Any</a>>, <br> right_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="enum.Error.html"title="enum halo2_proofs::plonk::Error">Error</a>></h4></div></summary><divclass="docblock"><p>Assign two cells to have the same value</p>
</div></details><detailsclass="rustdoc-toggle"open><summary><divid="tymethod.fill_from_row"class="method has-srclink"><divclass="rightside"><aclass="srclink"href="../../src/halo2_proofs/plonk/circuit.rs.html#372-377">source</a></div><h4class="code-header">fn <ahref="#tymethod.fill_from_row"class="fnname">fill_from_row</a>(<br> &mut self, <br> column: <aclass="struct"href="struct.Column.html"title="struct halo2_proofs::plonk::Column">Column</a><<aclass="struct"href="struct.Fixed.html"title="struct halo2_proofs::plonk::Fixed">Fixed</a>>, <br> row: <aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.usize.html">usize</a>, <br> to: <aclass="enum"href="https://doc.rust-lang.org/nightly/core/option/enum.Option.html"title="enum core::option::Option">Option</a><<aclass="enum"href="enum.Assigned.html"title="enum halo2_proofs::plonk::Assigned">Assigned</a><F>><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="enum.Error.html"title="enum halo2_proofs::plonk::Error">Error</a>></h4></div></summary><divclass="docblock"><p>Fills a fixed <code>column</code> starting from the given <code>row</code> with value <code>to</code>.</p>
</div></details><detailsclass="rustdoc-toggle"open><summary><divid="tymethod.push_namespace"class="method has-srclink"><divclass="rightside"><aclass="srclink"href="../../src/halo2_proofs/plonk/circuit.rs.html#384-387">source</a></div><h4class="code-header">fn <ahref="#tymethod.push_namespace"class="fnname">push_namespace</a><NR, N>(&mut self, name_fn: N) <spanclass="where fmt-newline">where<br> NR: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.Into.html"title="trait core::convert::Into">Into</a><<aclass="struct"href="https://doc.rust-lang.org/nightly/alloc/string/struct.String.html"title="struct alloc::string::String">String</a>>,<br> N: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/ops/function/trait.FnOnce.html"title="trait core::ops::function::FnOnce">FnOnce</a>() -> NR, </span></h4></div></summary><divclass="docblock"><p>Creates a new (sub)namespace and enters into it.</p>
<p>Not intended for downstream consumption; use <ahref="../circuit/trait.Layouter.html#method.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/plonk/circuit.rs.html#394">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="../circuit/trait.Layouter.html#method.namespace"><code>Layouter::namespace</code></a> instead.</p>
