| <!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="Source of the Rust file `crates/ide-ssr/src/fragments.rs`."><title>fragments.rs - source</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-77263533.css"><meta name="rustdoc-vars" data-root-path="../../" data-static-root-path="../../static.files/" data-current-crate="ide_ssr" data-themes="" data-resource-suffix="" data-rustdoc-version="1.94.0 (4a4ef493e 2026-03-02)" data-channel="1.94.0" data-search-js="search-9e2438ea.js" data-stringdex-js="stringdex-b897f86f.js" data-settings-js="settings-c38705f0.js" ><script src="../../static.files/storage-e2aeef58.js"></script><script defer src="../../static.files/src-script-813739b1.js"></script><script defer src="../../src-files.js"></script><script defer src="../../static.files/main-7bab91a1.js"></script><noscript><link rel="stylesheet" href="../../static.files/noscript-ffcac47a.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 src"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="src-sidebar-title"><h2>Files</h2></div></nav><div class="sidebar-resizer" title="Drag to resize sidebar"></div><main><section id="main-content" class="content"><div class="main-heading"><h1><div class="sub-heading">ide_ssr/</div>fragments.rs</h1><rustdoc-toolbar></rustdoc-toolbar></div><div class="example-wrap digits-2"><pre class="rust"><code><a href=#1 id=1 data-nosnippet>1</a><span class="doccomment">//! When specifying SSR rule, you generally want to map one *kind* of thing to |
| <a href=#2 id=2 data-nosnippet>2</a>//! the same kind of thing: path to path, expression to expression, type to |
| <a href=#3 id=3 data-nosnippet>3</a>//! type. |
| <a href=#4 id=4 data-nosnippet>4</a>//! |
| <a href=#5 id=5 data-nosnippet>5</a>//! The problem is, while this *kind* is generally obvious to the human, the ide |
| <a href=#6 id=6 data-nosnippet>6</a>//! needs to determine it somehow. We do this in a stupid way -- by pasting SSR |
| <a href=#7 id=7 data-nosnippet>7</a>//! rule into different contexts and checking what works. |
| <a href=#8 id=8 data-nosnippet>8</a> |
| <a href=#9 id=9 data-nosnippet>9</a></span><span class="kw">use </span>syntax::{AstNode, SyntaxNode, ast}; |
| <a href=#10 id=10 data-nosnippet>10</a> |
| <a href=#11 id=11 data-nosnippet>11</a><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>ty(s: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><SyntaxNode, ()> { |
| <a href=#12 id=12 data-nosnippet>12</a> fragment::<ast::Type>(<span class="string">"type T = {};"</span>, s) |
| <a href=#13 id=13 data-nosnippet>13</a>} |
| <a href=#14 id=14 data-nosnippet>14</a> |
| <a href=#15 id=15 data-nosnippet>15</a><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>item(s: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><SyntaxNode, ()> { |
| <a href=#16 id=16 data-nosnippet>16</a> fragment::<ast::Item>(<span class="string">"{}"</span>, s) |
| <a href=#17 id=17 data-nosnippet>17</a>} |
| <a href=#18 id=18 data-nosnippet>18</a> |
| <a href=#19 id=19 data-nosnippet>19</a><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>pat(s: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><SyntaxNode, ()> { |
| <a href=#20 id=20 data-nosnippet>20</a> fragment::<ast::Pat>(<span class="string">"const _: () = {let {} = ();};"</span>, s) |
| <a href=#21 id=21 data-nosnippet>21</a>} |
| <a href=#22 id=22 data-nosnippet>22</a> |
| <a href=#23 id=23 data-nosnippet>23</a><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>expr(s: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><SyntaxNode, ()> { |
| <a href=#24 id=24 data-nosnippet>24</a> fragment::<ast::Expr>(<span class="string">"const _: () = {};"</span>, s) |
| <a href=#25 id=25 data-nosnippet>25</a>} |
| <a href=#26 id=26 data-nosnippet>26</a> |
| <a href=#27 id=27 data-nosnippet>27</a><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>stmt(s: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><SyntaxNode, ()> { |
| <a href=#28 id=28 data-nosnippet>28</a> <span class="kw">let </span>template = <span class="string">"const _: () = { {}; };"</span>; |
| <a href=#29 id=29 data-nosnippet>29</a> <span class="kw">let </span>input = template.replace(<span class="string">"{}"</span>, s); |
| <a href=#30 id=30 data-nosnippet>30</a> <span class="kw">let </span>parse = syntax::SourceFile::parse(<span class="kw-2">&</span>input, syntax::Edition::CURRENT); |
| <a href=#31 id=31 data-nosnippet>31</a> <span class="kw">if </span>!parse.errors().is_empty() { |
| <a href=#32 id=32 data-nosnippet>32</a> <span class="kw">return </span><span class="prelude-val">Err</span>(()); |
| <a href=#33 id=33 data-nosnippet>33</a> } |
| <a href=#34 id=34 data-nosnippet>34</a> <span class="kw">let </span><span class="kw-2">mut </span>node = |
| <a href=#35 id=35 data-nosnippet>35</a> parse.tree().syntax().descendants().skip(<span class="number">2</span>).find_map(ast::Stmt::cast).ok_or(())<span class="question-mark">?</span>; |
| <a href=#36 id=36 data-nosnippet>36</a> <span class="kw">if </span>!s.ends_with(<span class="string">';'</span>) && node.to_string().ends_with(<span class="string">';'</span>) { |
| <a href=#37 id=37 data-nosnippet>37</a> node = node.clone_for_update(); |
| <a href=#38 id=38 data-nosnippet>38</a> <span class="kw">if let </span><span class="prelude-val">Some</span>(it) = node.syntax().last_token() { |
| <a href=#39 id=39 data-nosnippet>39</a> it.detach() |
| <a href=#40 id=40 data-nosnippet>40</a> } |
| <a href=#41 id=41 data-nosnippet>41</a> } |
| <a href=#42 id=42 data-nosnippet>42</a> <span class="kw">if </span>node.to_string() != s { |
| <a href=#43 id=43 data-nosnippet>43</a> <span class="kw">return </span><span class="prelude-val">Err</span>(()); |
| <a href=#44 id=44 data-nosnippet>44</a> } |
| <a href=#45 id=45 data-nosnippet>45</a> <span class="prelude-val">Ok</span>(node.syntax().clone_subtree()) |
| <a href=#46 id=46 data-nosnippet>46</a>} |
| <a href=#47 id=47 data-nosnippet>47</a> |
| <a href=#48 id=48 data-nosnippet>48</a><span class="kw">fn </span>fragment<T: AstNode>(template: <span class="kw-2">&</span>str, s: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><SyntaxNode, ()> { |
| <a href=#49 id=49 data-nosnippet>49</a> <span class="kw">let </span>s = s.trim(); |
| <a href=#50 id=50 data-nosnippet>50</a> <span class="kw">let </span>input = template.replace(<span class="string">"{}"</span>, s); |
| <a href=#51 id=51 data-nosnippet>51</a> <span class="kw">let </span>parse = syntax::SourceFile::parse(<span class="kw-2">&</span>input, syntax::Edition::CURRENT); |
| <a href=#52 id=52 data-nosnippet>52</a> <span class="kw">if </span>!parse.errors().is_empty() { |
| <a href=#53 id=53 data-nosnippet>53</a> <span class="kw">return </span><span class="prelude-val">Err</span>(()); |
| <a href=#54 id=54 data-nosnippet>54</a> } |
| <a href=#55 id=55 data-nosnippet>55</a> <span class="kw">let </span>node = parse.tree().syntax().descendants().find_map(T::cast).ok_or(())<span class="question-mark">?</span>; |
| <a href=#56 id=56 data-nosnippet>56</a> <span class="kw">if </span>node.syntax().text() != s { |
| <a href=#57 id=57 data-nosnippet>57</a> <span class="kw">return </span><span class="prelude-val">Err</span>(()); |
| <a href=#58 id=58 data-nosnippet>58</a> } |
| <a href=#59 id=59 data-nosnippet>59</a> <span class="prelude-val">Ok</span>(node.syntax().clone_subtree()) |
| <a href=#60 id=60 data-nosnippet>60</a>} |
| </code></pre></div></section></main></body></html> |
