| <!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 `TyKind` type in crate `hir_ty`."><title>TyKind in hir_ty::next_solver - Rust</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-6b053e98.ttf.woff2,FiraSans-Italic-81dc35de.woff2,FiraSans-Regular-0fe48ade.woff2,FiraSans-MediumItalic-ccf7e434.woff2,FiraSans-Medium-e1aa3f0a.woff2,SourceCodePro-Regular-8badfe75.ttf.woff2,SourceCodePro-Semibold-aa29a496.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2"href="../../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../../static.files/normalize-9960930a.css"><link rel="stylesheet" href="../../static.files/rustdoc-ca0dd0c4.css"><meta name="rustdoc-vars" data-root-path="../../" data-static-root-path="../../static.files/" data-current-crate="hir_ty" data-themes="" data-resource-suffix="" data-rustdoc-version="1.92.0 (ded5c06cf 2025-12-08)" data-channel="1.92.0" data-search-js="search-d69d8955.js" data-stringdex-js="stringdex-c3e638e9.js" data-settings-js="settings-c38705f0.js" ><script src="../../static.files/storage-e2aeef58.js"></script><script defer src="sidebar-items.js"></script><script defer src="../../static.files/main-ce535bd0.js"></script><noscript><link rel="stylesheet" href="../../static.files/noscript-263c88ec.css"></noscript><link rel="alternate icon" type="image/png" href="../../static.files/favicon-32x32-eab170b8.png"><link rel="icon" type="image/svg+xml" href="../../static.files/favicon-044be391.svg"></head><body class="rustdoc type"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><rustdoc-topbar><h2><a href="#">TyKind</a></h2></rustdoc-topbar><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../hir_ty/index.html">hir_ty</a><span class="version">0.0.0</span></h2></div><div class="sidebar-elems"><section id="rustdoc-toc"><h2 class="location"><a href="#">TyKind</a></h2><h3><a href="#aliased-type">Aliased Type</a></h3><h3><a href="#variants">Variants</a></h3><ul class="block variant"><li><a href="#variant.Adt" title="Adt">Adt</a></li><li><a href="#variant.Alias" title="Alias">Alias</a></li><li><a href="#variant.Array" title="Array">Array</a></li><li><a href="#variant.Bool" title="Bool">Bool</a></li><li><a href="#variant.Bound" title="Bound">Bound</a></li><li><a href="#variant.Char" title="Char">Char</a></li><li><a href="#variant.Closure" title="Closure">Closure</a></li><li><a href="#variant.Coroutine" title="Coroutine">Coroutine</a></li><li><a href="#variant.CoroutineClosure" title="CoroutineClosure">CoroutineClosure</a></li><li><a href="#variant.CoroutineWitness" title="CoroutineWitness">CoroutineWitness</a></li><li><a href="#variant.Dynamic" title="Dynamic">Dynamic</a></li><li><a href="#variant.Error" title="Error">Error</a></li><li><a href="#variant.Float" title="Float">Float</a></li><li><a href="#variant.FnDef" title="FnDef">FnDef</a></li><li><a href="#variant.FnPtr" title="FnPtr">FnPtr</a></li><li><a href="#variant.Foreign" title="Foreign">Foreign</a></li><li><a href="#variant.Infer" title="Infer">Infer</a></li><li><a href="#variant.Int" title="Int">Int</a></li><li><a href="#variant.Never" title="Never">Never</a></li><li><a href="#variant.Param" title="Param">Param</a></li><li><a href="#variant.Pat" title="Pat">Pat</a></li><li><a href="#variant.Placeholder" title="Placeholder">Placeholder</a></li><li><a href="#variant.RawPtr" title="RawPtr">RawPtr</a></li><li><a href="#variant.Ref" title="Ref">Ref</a></li><li><a href="#variant.Slice" title="Slice">Slice</a></li><li><a href="#variant.Str" title="Str">Str</a></li><li><a href="#variant.Tuple" title="Tuple">Tuple</a></li><li><a href="#variant.Uint" title="Uint">Uint</a></li><li><a href="#variant.UnsafeBinder" title="UnsafeBinder">UnsafeBinder</a></li></ul></section><div id="rustdoc-modnav"><h2><a href="index.html">In hir_<wbr>ty::<wbr>next_<wbr>solver</a></h2></div></div></nav><div class="sidebar-resizer" title="Drag to resize sidebar"></div><main><div class="width-limiter"><section id="main-content" class="content"><div class="main-heading"><div class="rustdoc-breadcrumbs"><a href="../index.html">hir_ty</a>::<wbr><a href="index.html">next_solver</a></div><h1>Type Alias <span class="type">TyKind</span> <button id="copy-path" title="Copy item path to clipboard">Copy item path</button></h1><rustdoc-toolbar></rustdoc-toolbar><span class="sub-heading"><a class="src" href="../../src/hir_ty/next_solver/ty.rs.html#44">Source</a> </span></div><pre class="rust item-decl"><code>pub type TyKind<'db> = TyKind<<a class="struct" href="interner/struct.DbInterner.html" title="struct hir_ty::next_solver::interner::DbInterner">DbInterner</a><'db>>;</code></pre><h2 id="aliased-type" class="section-header">Aliased Type<a href="#aliased-type" class="anchor">§</a></h2><pre class="rust item-decl"><code>pub enum TyKind<'db> { |
| <details class="toggle type-contents-toggle"><summary class="hideme"><span>Show 29 variants</span></summary> Bool, |
| Char, |
| Int(<a class="enum" href="../primitive/enum.IntTy.html" title="enum hir_ty::primitive::IntTy">IntTy</a>), |
| Uint(<a class="enum" href="../primitive/enum.UintTy.html" title="enum hir_ty::primitive::UintTy">UintTy</a>), |
| Float(<a class="enum" href="../primitive/enum.FloatTy.html" title="enum hir_ty::primitive::FloatTy">FloatTy</a>), |
| Adt(<a class="struct" href="interner/struct.AdtDef.html" title="struct hir_ty::next_solver::interner::AdtDef">AdtDef</a>, <a class="struct" href="struct.GenericArgs.html" title="struct hir_ty::next_solver::GenericArgs">GenericArgs</a><'db>), |
| Foreign(<a class="struct" href="struct.TypeAliasIdWrapper.html" title="struct hir_ty::next_solver::TypeAliasIdWrapper">TypeAliasIdWrapper</a>), |
| Str, |
| Array(<a class="struct" href="struct.Ty.html" title="struct hir_ty::next_solver::Ty">Ty</a><'db>, <a class="struct" href="struct.Const.html" title="struct hir_ty::next_solver::Const">Const</a><'db>), |
| Pat(<a class="struct" href="struct.Ty.html" title="struct hir_ty::next_solver::Ty">Ty</a><'db>, <a class="struct" href="interner/struct.Pattern.html" title="struct hir_ty::next_solver::interner::Pattern">Pattern</a><'db>), |
| Slice(<a class="struct" href="struct.Ty.html" title="struct hir_ty::next_solver::Ty">Ty</a><'db>), |
| RawPtr(<a class="struct" href="struct.Ty.html" title="struct hir_ty::next_solver::Ty">Ty</a><'db>, <a class="enum" href="enum.Mutability.html" title="enum hir_ty::next_solver::Mutability">Mutability</a>), |
| Ref(<a class="struct" href="struct.Region.html" title="struct hir_ty::next_solver::Region">Region</a><'db>, <a class="struct" href="struct.Ty.html" title="struct hir_ty::next_solver::Ty">Ty</a><'db>, <a class="enum" href="enum.Mutability.html" title="enum hir_ty::next_solver::Mutability">Mutability</a>), |
| FnDef(<a class="struct" href="struct.CallableIdWrapper.html" title="struct hir_ty::next_solver::CallableIdWrapper">CallableIdWrapper</a>, <a class="struct" href="struct.GenericArgs.html" title="struct hir_ty::next_solver::GenericArgs">GenericArgs</a><'db>), |
| FnPtr(Binder<<a class="struct" href="interner/struct.DbInterner.html" title="struct hir_ty::next_solver::interner::DbInterner">DbInterner</a><'db>, FnSigTys<<a class="struct" href="interner/struct.DbInterner.html" title="struct hir_ty::next_solver::interner::DbInterner">DbInterner</a><'db>>>, FnHeader<<a class="struct" href="interner/struct.DbInterner.html" title="struct hir_ty::next_solver::interner::DbInterner">DbInterner</a><'db>>), |
| UnsafeBinder(UnsafeBinderInner<<a class="struct" href="interner/struct.DbInterner.html" title="struct hir_ty::next_solver::interner::DbInterner">DbInterner</a><'db>>), |
| Dynamic(<a class="struct" href="predicate/struct.BoundExistentialPredicates.html" title="struct hir_ty::next_solver::predicate::BoundExistentialPredicates">BoundExistentialPredicates</a><'db>, <a class="struct" href="struct.Region.html" title="struct hir_ty::next_solver::Region">Region</a><'db>), |
| Closure(<a class="struct" href="struct.ClosureIdWrapper.html" title="struct hir_ty::next_solver::ClosureIdWrapper">ClosureIdWrapper</a>, <a class="struct" href="struct.GenericArgs.html" title="struct hir_ty::next_solver::GenericArgs">GenericArgs</a><'db>), |
| CoroutineClosure(<a class="struct" href="struct.CoroutineIdWrapper.html" title="struct hir_ty::next_solver::CoroutineIdWrapper">CoroutineIdWrapper</a>, <a class="struct" href="struct.GenericArgs.html" title="struct hir_ty::next_solver::GenericArgs">GenericArgs</a><'db>), |
| Coroutine(<a class="struct" href="struct.CoroutineIdWrapper.html" title="struct hir_ty::next_solver::CoroutineIdWrapper">CoroutineIdWrapper</a>, <a class="struct" href="struct.GenericArgs.html" title="struct hir_ty::next_solver::GenericArgs">GenericArgs</a><'db>), |
| CoroutineWitness(<a class="struct" href="struct.CoroutineIdWrapper.html" title="struct hir_ty::next_solver::CoroutineIdWrapper">CoroutineIdWrapper</a>, <a class="struct" href="struct.GenericArgs.html" title="struct hir_ty::next_solver::GenericArgs">GenericArgs</a><'db>), |
| Never, |
| Tuple(<a class="struct" href="struct.Tys.html" title="struct hir_ty::next_solver::Tys">Tys</a><'db>), |
| Alias(AliasTyKind, AliasTy<<a class="struct" href="interner/struct.DbInterner.html" title="struct hir_ty::next_solver::interner::DbInterner">DbInterner</a><'db>>), |
| Param(<a class="struct" href="struct.ParamTy.html" title="struct hir_ty::next_solver::ParamTy">ParamTy</a>), |
| Bound(BoundVarIndexKind, <a class="struct" href="struct.BoundTy.html" title="struct hir_ty::next_solver::BoundTy">BoundTy</a>), |
| Placeholder(<a class="struct" href="interner/struct.Placeholder.html" title="struct hir_ty::next_solver::interner::Placeholder">Placeholder</a><<a class="struct" href="struct.BoundTy.html" title="struct hir_ty::next_solver::BoundTy">BoundTy</a>>), |
| Infer(InferTy), |
| Error(<a class="struct" href="struct.ErrorGuaranteed.html" title="struct hir_ty::next_solver::ErrorGuaranteed">ErrorGuaranteed</a>), |
| </details>}</code></pre><h2 id="variants" class="variants section-header">Variants<a href="#variants" class="anchor">§</a></h2><div class="variants"><section id="variant.Bool" class="variant"><a href="#variant.Bool" class="anchor">§</a><h3 class="code-header">Bool</h3></section><div class="docblock"><p>The primitive boolean type. Written as <code>bool</code>.</p> |
| </div><section id="variant.Char" class="variant"><a href="#variant.Char" class="anchor">§</a><h3 class="code-header">Char</h3></section><div class="docblock"><p>The primitive character type; holds a Unicode scalar value |
| (a non-surrogate code point). Written as <code>char</code>.</p> |
| </div><section id="variant.Int" class="variant"><a href="#variant.Int" class="anchor">§</a><h3 class="code-header">Int(<a class="enum" href="../primitive/enum.IntTy.html" title="enum hir_ty::primitive::IntTy">IntTy</a>)</h3></section><div class="docblock"><p>A primitive signed integer type. For example, <code>i32</code>.</p> |
| </div><section id="variant.Uint" class="variant"><a href="#variant.Uint" class="anchor">§</a><h3 class="code-header">Uint(<a class="enum" href="../primitive/enum.UintTy.html" title="enum hir_ty::primitive::UintTy">UintTy</a>)</h3></section><div class="docblock"><p>A primitive unsigned integer type. For example, <code>u32</code>.</p> |
| </div><section id="variant.Float" class="variant"><a href="#variant.Float" class="anchor">§</a><h3 class="code-header">Float(<a class="enum" href="../primitive/enum.FloatTy.html" title="enum hir_ty::primitive::FloatTy">FloatTy</a>)</h3></section><div class="docblock"><p>A primitive floating-point type. For example, <code>f64</code>.</p> |
| </div><section id="variant.Adt" class="variant"><a href="#variant.Adt" class="anchor">§</a><h3 class="code-header">Adt(<a class="struct" href="interner/struct.AdtDef.html" title="struct hir_ty::next_solver::interner::AdtDef">AdtDef</a>, <a class="struct" href="struct.GenericArgs.html" title="struct hir_ty::next_solver::GenericArgs">GenericArgs</a><'db>)</h3></section><div class="docblock"><p>Algebraic data types (ADT). For example: structures, enumerations and unions.</p> |
| <p>For example, the type <code>List<i32></code> would be represented using the <code>AdtDef</code> |
| for <code>struct List<T></code> and the args <code>[i32]</code>.</p> |
| <p>Note that generic parameters in fields only get lazily instantiated |
| by using something like <code>adt_def.all_fields().map(|field| field.ty(interner, args))</code>.</p> |
| </div><section id="variant.Foreign" class="variant"><a href="#variant.Foreign" class="anchor">§</a><h3 class="code-header">Foreign(<a class="struct" href="struct.TypeAliasIdWrapper.html" title="struct hir_ty::next_solver::TypeAliasIdWrapper">TypeAliasIdWrapper</a>)</h3></section><div class="docblock"><p>An unsized FFI type that is opaque to Rust. Written as <code>extern type T</code>.</p> |
| </div><section id="variant.Str" class="variant"><a href="#variant.Str" class="anchor">§</a><h3 class="code-header">Str</h3></section><div class="docblock"><p>The pointee of a string slice. Written as <code>str</code>.</p> |
| </div><section id="variant.Array" class="variant"><a href="#variant.Array" class="anchor">§</a><h3 class="code-header">Array(<a class="struct" href="struct.Ty.html" title="struct hir_ty::next_solver::Ty">Ty</a><'db>, <a class="struct" href="struct.Const.html" title="struct hir_ty::next_solver::Const">Const</a><'db>)</h3></section><div class="docblock"><p>An array with the given length. Written as <code>[T; N]</code>.</p> |
| </div><section id="variant.Pat" class="variant"><a href="#variant.Pat" class="anchor">§</a><h3 class="code-header">Pat(<a class="struct" href="struct.Ty.html" title="struct hir_ty::next_solver::Ty">Ty</a><'db>, <a class="struct" href="interner/struct.Pattern.html" title="struct hir_ty::next_solver::interner::Pattern">Pattern</a><'db>)</h3></section><div class="docblock"><p>A pattern newtype. Takes any type and restricts its valid values to its pattern. |
| This will also change the layout to take advantage of this restriction. |
| Only <code>Copy</code> and <code>Clone</code> will automatically get implemented for pattern types. |
| Auto-traits treat this as if it were an aggregate with a single nested type. |
| Only supports integer range patterns for now.</p> |
| </div><section id="variant.Slice" class="variant"><a href="#variant.Slice" class="anchor">§</a><h3 class="code-header">Slice(<a class="struct" href="struct.Ty.html" title="struct hir_ty::next_solver::Ty">Ty</a><'db>)</h3></section><div class="docblock"><p>The pointee of an array slice. Written as <code>[T]</code>.</p> |
| </div><section id="variant.RawPtr" class="variant"><a href="#variant.RawPtr" class="anchor">§</a><h3 class="code-header">RawPtr(<a class="struct" href="struct.Ty.html" title="struct hir_ty::next_solver::Ty">Ty</a><'db>, <a class="enum" href="enum.Mutability.html" title="enum hir_ty::next_solver::Mutability">Mutability</a>)</h3></section><div class="docblock"><p>A raw pointer. Written as <code>*mut T</code> or <code>*const T</code></p> |
| </div><section id="variant.Ref" class="variant"><a href="#variant.Ref" class="anchor">§</a><h3 class="code-header">Ref(<a class="struct" href="struct.Region.html" title="struct hir_ty::next_solver::Region">Region</a><'db>, <a class="struct" href="struct.Ty.html" title="struct hir_ty::next_solver::Ty">Ty</a><'db>, <a class="enum" href="enum.Mutability.html" title="enum hir_ty::next_solver::Mutability">Mutability</a>)</h3></section><div class="docblock"><p>A reference; a pointer with an associated lifetime. Written as |
| <code>&'a mut T</code> or <code>&'a T</code>.</p> |
| </div><section id="variant.FnDef" class="variant"><a href="#variant.FnDef" class="anchor">§</a><h3 class="code-header">FnDef(<a class="struct" href="struct.CallableIdWrapper.html" title="struct hir_ty::next_solver::CallableIdWrapper">CallableIdWrapper</a>, <a class="struct" href="struct.GenericArgs.html" title="struct hir_ty::next_solver::GenericArgs">GenericArgs</a><'db>)</h3></section><div class="docblock"><p>The anonymous type of a function declaration/definition. Each |
| function has a unique type.</p> |
| <p>For the function <code>fn foo() -> i32 { 3 }</code> this type would be |
| shown to the user as <code>fn() -> i32 {foo}</code>.</p> |
| <p>For example the type of <code>bar</code> here:</p> |
| |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">fn </span>foo() -> i32 { <span class="number">1 </span>} |
| <span class="kw">let </span>bar = foo; <span class="comment">// bar: fn() -> i32 {foo}</span></code></pre></div></div><section id="variant.FnPtr" class="variant"><a href="#variant.FnPtr" class="anchor">§</a><h3 class="code-header">FnPtr(Binder<<a class="struct" href="interner/struct.DbInterner.html" title="struct hir_ty::next_solver::interner::DbInterner">DbInterner</a><'db>, FnSigTys<<a class="struct" href="interner/struct.DbInterner.html" title="struct hir_ty::next_solver::interner::DbInterner">DbInterner</a><'db>>>, FnHeader<<a class="struct" href="interner/struct.DbInterner.html" title="struct hir_ty::next_solver::interner::DbInterner">DbInterner</a><'db>>)</h3></section><div class="docblock"><p>A pointer to a function. Written as <code>fn() -> i32</code>.</p> |
| <p>Note that both functions and closures start out as either |
| [FnDef] or [Closure] which can be then be coerced to this variant.</p> |
| <p>For example the type of <code>bar</code> here:</p> |
| |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">fn </span>foo() -> i32 { <span class="number">1 </span>} |
| <span class="kw">let </span>bar: <span class="kw">fn</span>() -> i32 = foo;</code></pre></div> |
| <p>These two fields are equivalent to a <code>ty::Binder<I, FnSig<I>></code>. But by |
| splitting that into two pieces, we get a more compact data layout that |
| reduces the size of <code>TyKind</code> by 8 bytes. It is a very hot type, so it’s |
| worth the mild inconvenience.</p> |
| </div><section id="variant.UnsafeBinder" class="variant"><a href="#variant.UnsafeBinder" class="anchor">§</a><h3 class="code-header">UnsafeBinder(UnsafeBinderInner<<a class="struct" href="interner/struct.DbInterner.html" title="struct hir_ty::next_solver::interner::DbInterner">DbInterner</a><'db>>)</h3></section><div class="docblock"><p>An unsafe binder type.</p> |
| <p>A higher-ranked type used to represent a type which has had some of its |
| lifetimes erased. This can be used to represent types in positions where |
| a lifetime is literally inexpressible, such as self-referential types.</p> |
| </div><section id="variant.Dynamic" class="variant"><a href="#variant.Dynamic" class="anchor">§</a><h3 class="code-header">Dynamic(<a class="struct" href="predicate/struct.BoundExistentialPredicates.html" title="struct hir_ty::next_solver::predicate::BoundExistentialPredicates">BoundExistentialPredicates</a><'db>, <a class="struct" href="struct.Region.html" title="struct hir_ty::next_solver::Region">Region</a><'db>)</h3></section><div class="docblock"><p>A trait object. Written as <code>dyn for<'b> Trait<'b, Assoc = u32> + Send + 'a</code>.</p> |
| </div><section id="variant.Closure" class="variant"><a href="#variant.Closure" class="anchor">§</a><h3 class="code-header">Closure(<a class="struct" href="struct.ClosureIdWrapper.html" title="struct hir_ty::next_solver::ClosureIdWrapper">ClosureIdWrapper</a>, <a class="struct" href="struct.GenericArgs.html" title="struct hir_ty::next_solver::GenericArgs">GenericArgs</a><'db>)</h3></section><div class="docblock"><p>The anonymous type of a closure. Used to represent the type of <code>|a| a</code>.</p> |
| <p>Closure args contain both the - potentially instantiated - generic parameters |
| of its parent and some synthetic parameters. See the documentation for |
| <code>ClosureArgs</code> for more details.</p> |
| </div><section id="variant.CoroutineClosure" class="variant"><a href="#variant.CoroutineClosure" class="anchor">§</a><h3 class="code-header">CoroutineClosure(<a class="struct" href="struct.CoroutineIdWrapper.html" title="struct hir_ty::next_solver::CoroutineIdWrapper">CoroutineIdWrapper</a>, <a class="struct" href="struct.GenericArgs.html" title="struct hir_ty::next_solver::GenericArgs">GenericArgs</a><'db>)</h3></section><div class="docblock"><p>The anonymous type of a closure. Used to represent the type of <code>async |a| a</code>.</p> |
| <p>Coroutine-closure args contain both the - potentially instantiated - generic |
| parameters of its parent and some synthetic parameters. See the documentation |
| for <code>CoroutineClosureArgs</code> for more details.</p> |
| </div><section id="variant.Coroutine" class="variant"><a href="#variant.Coroutine" class="anchor">§</a><h3 class="code-header">Coroutine(<a class="struct" href="struct.CoroutineIdWrapper.html" title="struct hir_ty::next_solver::CoroutineIdWrapper">CoroutineIdWrapper</a>, <a class="struct" href="struct.GenericArgs.html" title="struct hir_ty::next_solver::GenericArgs">GenericArgs</a><'db>)</h3></section><div class="docblock"><p>The anonymous type of a coroutine. Used to represent the type of |
| <code>|a| yield a</code>.</p> |
| <p>For more info about coroutine args, visit the documentation for |
| <code>CoroutineArgs</code>.</p> |
| </div><section id="variant.CoroutineWitness" class="variant"><a href="#variant.CoroutineWitness" class="anchor">§</a><h3 class="code-header">CoroutineWitness(<a class="struct" href="struct.CoroutineIdWrapper.html" title="struct hir_ty::next_solver::CoroutineIdWrapper">CoroutineIdWrapper</a>, <a class="struct" href="struct.GenericArgs.html" title="struct hir_ty::next_solver::GenericArgs">GenericArgs</a><'db>)</h3></section><div class="docblock"><p>A type representing the types stored inside a coroutine. |
| This should only appear as part of the <code>CoroutineArgs</code>.</p> |
| <p>Unlike upvars, the witness can reference lifetimes from |
| inside of the coroutine itself. To deal with them in |
| the type of the coroutine, we convert them to higher ranked |
| lifetimes bound by the witness itself.</p> |
| <p>This contains the <code>DefId</code> and the <code>GenericArgsRef</code> of the coroutine. |
| The actual witness types are computed on MIR by the <code>mir_coroutine_witnesses</code> query.</p> |
| <p>Looking at the following example, the witness for this coroutine |
| may end up as something like <code>for<'a> [Vec<i32>, &'a Vec<i32>]</code>:</p> |
| |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="attr">#![feature(coroutines)] |
| #[coroutine] </span><span class="kw">static </span>|a| { |
| <span class="kw">let </span>x = <span class="kw-2">&</span><span class="macro">vec!</span>[<span class="number">3</span>]; |
| <span class="kw">yield </span>a; |
| <span class="kw">yield </span>x[<span class="number">0</span>]; |
| }</code></pre></div></div><section id="variant.Never" class="variant"><a href="#variant.Never" class="anchor">§</a><h3 class="code-header">Never</h3></section><div class="docblock"><p>The never type <code>!</code>.</p> |
| </div><section id="variant.Tuple" class="variant"><a href="#variant.Tuple" class="anchor">§</a><h3 class="code-header">Tuple(<a class="struct" href="struct.Tys.html" title="struct hir_ty::next_solver::Tys">Tys</a><'db>)</h3></section><div class="docblock"><p>A tuple type. For example, <code>(i32, bool)</code>.</p> |
| </div><section id="variant.Alias" class="variant"><a href="#variant.Alias" class="anchor">§</a><h3 class="code-header">Alias(AliasTyKind, AliasTy<<a class="struct" href="interner/struct.DbInterner.html" title="struct hir_ty::next_solver::interner::DbInterner">DbInterner</a><'db>>)</h3></section><div class="docblock"><p>A projection, opaque type, free type alias, or inherent associated type. |
| All of these types are represented as pairs of def-id and args, and can |
| be normalized, so they are grouped conceptually.</p> |
| </div><section id="variant.Param" class="variant"><a href="#variant.Param" class="anchor">§</a><h3 class="code-header">Param(<a class="struct" href="struct.ParamTy.html" title="struct hir_ty::next_solver::ParamTy">ParamTy</a>)</h3></section><div class="docblock"><p>A type parameter; for example, <code>T</code> in <code>fn f<T>(x: T) {}</code>.</p> |
| </div><section id="variant.Bound" class="variant"><a href="#variant.Bound" class="anchor">§</a><h3 class="code-header">Bound(BoundVarIndexKind, <a class="struct" href="struct.BoundTy.html" title="struct hir_ty::next_solver::BoundTy">BoundTy</a>)</h3></section><div class="docblock"><p>Bound type variable, used to represent the <code>'a</code> in <code>for<'a> fn(&'a ())</code>.</p> |
| <p>For canonical queries, we replace inference variables with bound variables, |
| so e.g. when checking whether <code>&'_ (): Trait<_></code> holds, we canonicalize that to |
| <code>for<'a, T> &'a (): Trait<T></code> and then convert the introduced bound variables |
| back to inference variables in a new inference context when inside of the query.</p> |
| <p>It is conventional to render anonymous bound types like <code>^N</code> or <code>^D_N</code>, |
| where <code>N</code> is the bound variable’s anonymous index into the binder, and |
| <code>D</code> is the debruijn index, or totally omitted if the debruijn index is zero.</p> |
| <p>See the <code>rustc-dev-guide</code> for more details about |
| <a href="https://rustc-dev-guide.rust-lang.org/traits/hrtb.html">higher-ranked trait bounds</a> and <a href="https://rustc-dev-guide.rust-lang.org/traits/canonical-queries.html">canonical queries</a>.</p> |
| </div><section id="variant.Placeholder" class="variant"><a href="#variant.Placeholder" class="anchor">§</a><h3 class="code-header">Placeholder(<a class="struct" href="interner/struct.Placeholder.html" title="struct hir_ty::next_solver::interner::Placeholder">Placeholder</a><<a class="struct" href="struct.BoundTy.html" title="struct hir_ty::next_solver::BoundTy">BoundTy</a>>)</h3></section><div class="docblock"><p>A placeholder type, used during higher ranked subtyping to instantiate |
| bound variables.</p> |
| <p>It is conventional to render anonymous placeholder types like <code>!N</code> or <code>!U_N</code>, |
| where <code>N</code> is the placeholder variable’s anonymous index (which corresponds |
| to the bound variable’s index from the binder from which it was instantiated), |
| and <code>U</code> is the universe index in which it is instantiated, or totally omitted |
| if the universe index is zero.</p> |
| </div><section id="variant.Infer" class="variant"><a href="#variant.Infer" class="anchor">§</a><h3 class="code-header">Infer(InferTy)</h3></section><div class="docblock"><p>A type variable used during type checking.</p> |
| <p>Similar to placeholders, inference variables also live in a universe to |
| correctly deal with higher ranked types. Though unlike placeholders, |
| that universe is stored in the <code>InferCtxt</code> instead of directly |
| inside of the type.</p> |
| </div><section id="variant.Error" class="variant"><a href="#variant.Error" class="anchor">§</a><h3 class="code-header">Error(<a class="struct" href="struct.ErrorGuaranteed.html" title="struct hir_ty::next_solver::ErrorGuaranteed">ErrorGuaranteed</a>)</h3></section><div class="docblock"><p>A placeholder for a type which could not be computed; this is |
| propagated to avoid useless error messages.</p> |
| </div></div><script src="../../type.impl/ra_ap_rustc_type_ir/ty_kind/enum.TyKind.js" data-self-path="hir_ty::next_solver::ty::TyKind" async></script></section></div></main></body></html> |
