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<a href=#2 id=2 data-nosnippet>2</a>//!
<a href=#3 id=3 data-nosnippet>3</a>//! See [`crate::intern`] for an explanation of interning modes. Note that slice interning is currently
<a href=#4 id=4 data-nosnippet>4</a>//! available only in GC mode (there is no other need).
<a href=#5 id=5 data-nosnippet>5</a>//!
<a href=#6 id=6 data-nosnippet>6</a>//! [`InternedSlice`] and [`InternedSliceRef`] are essentially [`Interned&lt;(Header, Box&lt;[SliceType]&gt;)&gt;`][crate::Interned]
<a href=#7 id=7 data-nosnippet>7</a>//! and [`InternedRef`][crate::InternedRef] with the same types, but more optimized. There is only one
<a href=#8 id=8 data-nosnippet>8</a>//! allocation and the pointer is thin.
<a href=#9 id=9 data-nosnippet>9</a>
<a href=#10 id=10 data-nosnippet>10</a></span><span class="kw">use </span>std::{
<a href=#11 id=11 data-nosnippet>11</a> ffi::c_void,
<a href=#12 id=12 data-nosnippet>12</a> fmt::{<span class="self">self</span>, Debug},
<a href=#13 id=13 data-nosnippet>13</a> hash::{BuildHasher, Hash, Hasher},
<a href=#14 id=14 data-nosnippet>14</a> marker::PhantomData,
<a href=#15 id=15 data-nosnippet>15</a> mem::ManuallyDrop,
<a href=#16 id=16 data-nosnippet>16</a> ops::Deref,
<a href=#17 id=17 data-nosnippet>17</a> ptr::{<span class="self">self</span>, NonNull},
<a href=#18 id=18 data-nosnippet>18</a> sync::OnceLock,
<a href=#19 id=19 data-nosnippet>19</a>};
<a href=#20 id=20 data-nosnippet>20</a>
<a href=#21 id=21 data-nosnippet>21</a><span class="kw">use </span>dashmap::{DashMap, SharedValue};
<a href=#22 id=22 data-nosnippet>22</a><span class="kw">use </span>hashbrown::raw::RawTable;
<a href=#23 id=23 data-nosnippet>23</a><span class="kw">use </span>rustc_hash::FxBuildHasher;
<a href=#24 id=24 data-nosnippet>24</a><span class="kw">use </span>triomphe::{HeaderSlice, HeaderWithLength, ThinArc};
<a href=#25 id=25 data-nosnippet>25</a>
<a href=#26 id=26 data-nosnippet>26</a><span class="kw">type </span>InternMap&lt;T&gt; = DashMap&lt;
<a href=#27 id=27 data-nosnippet>27</a> ThinArc&lt;&lt;T <span class="kw">as </span>SliceInternable&gt;::Header, &lt;T <span class="kw">as </span>SliceInternable&gt;::SliceType&gt;,
<a href=#28 id=28 data-nosnippet>28</a> (),
<a href=#29 id=29 data-nosnippet>29</a> FxBuildHasher,
<a href=#30 id=30 data-nosnippet>30</a>&gt;;
<a href=#31 id=31 data-nosnippet>31</a><span class="kw">type </span>Guard&lt;T&gt; = dashmap::RwLockWriteGuard&lt;
<a href=#32 id=32 data-nosnippet>32</a> <span class="lifetime">'static</span>,
<a href=#33 id=33 data-nosnippet>33</a> RawTable&lt;(
<a href=#34 id=34 data-nosnippet>34</a> ThinArc&lt;&lt;T <span class="kw">as </span>SliceInternable&gt;::Header, &lt;T <span class="kw">as </span>SliceInternable&gt;::SliceType&gt;,
<a href=#35 id=35 data-nosnippet>35</a> SharedValue&lt;()&gt;,
<a href=#36 id=36 data-nosnippet>36</a> )&gt;,
<a href=#37 id=37 data-nosnippet>37</a>&gt;;
<a href=#38 id=38 data-nosnippet>38</a><span class="kw">type </span>Pointee&lt;T&gt; = HeaderSlice&lt;
<a href=#39 id=39 data-nosnippet>39</a> HeaderWithLength&lt;&lt;T <span class="kw">as </span>SliceInternable&gt;::Header&gt;,
<a href=#40 id=40 data-nosnippet>40</a> [&lt;T <span class="kw">as </span>SliceInternable&gt;::SliceType],
<a href=#41 id=41 data-nosnippet>41</a>&gt;;
<a href=#42 id=42 data-nosnippet>42</a>
<a href=#43 id=43 data-nosnippet>43</a><span class="kw">pub struct </span>InternedSlice&lt;T: SliceInternable&gt; {
<a href=#44 id=44 data-nosnippet>44</a> arc: ThinArc&lt;T::Header, T::SliceType&gt;,
<a href=#45 id=45 data-nosnippet>45</a>}
<a href=#46 id=46 data-nosnippet>46</a>
<a href=#47 id=47 data-nosnippet>47</a><span class="kw">impl</span>&lt;T: SliceInternable&gt; InternedSlice&lt;T&gt; {
<a href=#48 id=48 data-nosnippet>48</a> <span class="attr">#[inline]
<a href=#49 id=49 data-nosnippet>49</a> </span><span class="kw">pub fn </span>from_header_and_slice&lt;<span class="lifetime">'a</span>&gt;(
<a href=#50 id=50 data-nosnippet>50</a> header: T::Header,
<a href=#51 id=51 data-nosnippet>51</a> slice: <span class="kw-2">&amp;</span>[T::SliceType],
<a href=#52 id=52 data-nosnippet>52</a> ) -&gt; InternedSliceRef&lt;<span class="lifetime">'a</span>, T&gt; {
<a href=#53 id=53 data-nosnippet>53</a> <span class="kw">const </span>{ <span class="macro">assert!</span>(T::USE_GC) };
<a href=#54 id=54 data-nosnippet>54</a>
<a href=#55 id=55 data-nosnippet>55</a> <span class="kw">let </span>storage = T::storage().get();
<a href=#56 id=56 data-nosnippet>56</a> <span class="kw">let </span>(<span class="kw-2">mut </span>shard, hash) = <span class="self">Self</span>::select(storage, <span class="kw-2">&amp;</span>header, slice);
<a href=#57 id=57 data-nosnippet>57</a> <span class="comment">// Atomically,
<a href=#58 id=58 data-nosnippet>58</a> // - check if `obj` is already in the map
<a href=#59 id=59 data-nosnippet>59</a> // - if so, clone its `Arc` and return it
<a href=#60 id=60 data-nosnippet>60</a> // - if not, box it up, insert it, and return a clone
<a href=#61 id=61 data-nosnippet>61</a> // This needs to be atomic (locking the shard) to avoid races with other thread, which could
<a href=#62 id=62 data-nosnippet>62</a> // insert the same object between us looking it up and inserting it.
<a href=#63 id=63 data-nosnippet>63</a> </span><span class="kw">let </span>bucket = <span class="kw">match </span>shard.find_or_find_insert_slot(
<a href=#64 id=64 data-nosnippet>64</a> hash,
<a href=#65 id=65 data-nosnippet>65</a> |(other, <span class="kw">_</span>)| other.header.header == header &amp;&amp; other.slice == <span class="kw-2">*</span>slice,
<a href=#66 id=66 data-nosnippet>66</a> |(x, <span class="kw">_</span>)| storage.hasher().hash_one(x),
<a href=#67 id=67 data-nosnippet>67</a> ) {
<a href=#68 id=68 data-nosnippet>68</a> <span class="prelude-val">Ok</span>(bucket) =&gt; bucket,
<a href=#69 id=69 data-nosnippet>69</a> <span class="comment">// SAFETY: The slot came from `find_or_find_insert_slot()`, and the table wasn't modified since then.
<a href=#70 id=70 data-nosnippet>70</a> </span><span class="prelude-val">Err</span>(insert_slot) =&gt; <span class="kw">unsafe </span>{
<a href=#71 id=71 data-nosnippet>71</a> shard.insert_in_slot(
<a href=#72 id=72 data-nosnippet>72</a> hash,
<a href=#73 id=73 data-nosnippet>73</a> insert_slot,
<a href=#74 id=74 data-nosnippet>74</a> (ThinArc::from_header_and_slice(header, slice), SharedValue::new(())),
<a href=#75 id=75 data-nosnippet>75</a> )
<a href=#76 id=76 data-nosnippet>76</a> },
<a href=#77 id=77 data-nosnippet>77</a> };
<a href=#78 id=78 data-nosnippet>78</a> <span class="comment">// SAFETY: We just retrieved/inserted this bucket.
<a href=#79 id=79 data-nosnippet>79</a> // `NonNull::new_unchecked()` is safe because the pointer originates from a `ThinArc`.
<a href=#80 id=80 data-nosnippet>80</a> </span><span class="kw">unsafe </span>{
<a href=#81 id=81 data-nosnippet>81</a> InternedSliceRef {
<a href=#82 id=82 data-nosnippet>82</a> <span class="comment">// INVARIANT: We create it from a `ThinArc`.
<a href=#83 id=83 data-nosnippet>83</a> </span>ptr: NonNull::new_unchecked(ThinArc::as_ptr(<span class="kw-2">&amp;</span>bucket.as_ref().<span class="number">0</span>).cast_mut()),
<a href=#84 id=84 data-nosnippet>84</a> _marker: PhantomData,
<a href=#85 id=85 data-nosnippet>85</a> }
<a href=#86 id=86 data-nosnippet>86</a> }
<a href=#87 id=87 data-nosnippet>87</a> }
<a href=#88 id=88 data-nosnippet>88</a>
<a href=#89 id=89 data-nosnippet>89</a> <span class="attr">#[inline]
<a href=#90 id=90 data-nosnippet>90</a> </span><span class="kw">fn </span>select(
<a href=#91 id=91 data-nosnippet>91</a> storage: <span class="kw-2">&amp;</span><span class="lifetime">'static </span>InternMap&lt;T&gt;,
<a href=#92 id=92 data-nosnippet>92</a> header: <span class="kw-2">&amp;</span>T::Header,
<a href=#93 id=93 data-nosnippet>93</a> slice: <span class="kw-2">&amp;</span>[T::SliceType],
<a href=#94 id=94 data-nosnippet>94</a> ) -&gt; (Guard&lt;T&gt;, u64) {
<a href=#95 id=95 data-nosnippet>95</a> <span class="kw">let </span>hash = <span class="self">Self</span>::hash(storage, header, slice);
<a href=#96 id=96 data-nosnippet>96</a> <span class="kw">let </span>shard_idx = storage.determine_shard(hash <span class="kw">as </span>usize);
<a href=#97 id=97 data-nosnippet>97</a> <span class="kw">let </span>shard = <span class="kw-2">&amp;</span>storage.shards()[shard_idx];
<a href=#98 id=98 data-nosnippet>98</a> (shard.write(), hash)
<a href=#99 id=99 data-nosnippet>99</a> }
<a href=#100 id=100 data-nosnippet>100</a>
<a href=#101 id=101 data-nosnippet>101</a> <span class="attr">#[inline]
<a href=#102 id=102 data-nosnippet>102</a> </span><span class="kw">fn </span>hash(storage: <span class="kw-2">&amp;</span><span class="lifetime">'static </span>InternMap&lt;T&gt;, header: <span class="kw-2">&amp;</span>T::Header, slice: <span class="kw-2">&amp;</span>[T::SliceType]) -&gt; u64 {
<a href=#103 id=103 data-nosnippet>103</a> storage.hasher().hash_one(HeaderSlice {
<a href=#104 id=104 data-nosnippet>104</a> header: HeaderWithLength { header, length: slice.len() },
<a href=#105 id=105 data-nosnippet>105</a> slice,
<a href=#106 id=106 data-nosnippet>106</a> })
<a href=#107 id=107 data-nosnippet>107</a> }
<a href=#108 id=108 data-nosnippet>108</a>
<a href=#109 id=109 data-nosnippet>109</a> <span class="attr">#[inline(always)]
<a href=#110 id=110 data-nosnippet>110</a> </span><span class="kw">fn </span>ptr(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; <span class="kw-2">*const </span>c_void {
<a href=#111 id=111 data-nosnippet>111</a> <span class="self">self</span>.arc.as_ptr()
<a href=#112 id=112 data-nosnippet>112</a> }
<a href=#113 id=113 data-nosnippet>113</a>
<a href=#114 id=114 data-nosnippet>114</a> <span class="attr">#[inline]
<a href=#115 id=115 data-nosnippet>115</a> </span><span class="kw">pub fn </span>as_ref(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; InternedSliceRef&lt;<span class="lifetime">'_</span>, T&gt; {
<a href=#116 id=116 data-nosnippet>116</a> InternedSliceRef {
<a href=#117 id=117 data-nosnippet>117</a> <span class="comment">// SAFETY: `self.ptr` comes from a valid `ThinArc`, so non null.
<a href=#118 id=118 data-nosnippet>118</a> // INVARIANT: We create it from a `ThinArc`.
<a href=#119 id=119 data-nosnippet>119</a> </span>ptr: <span class="kw">unsafe </span>{ NonNull::new_unchecked(<span class="self">self</span>.ptr().cast_mut()) },
<a href=#120 id=120 data-nosnippet>120</a> _marker: PhantomData,
<a href=#121 id=121 data-nosnippet>121</a> }
<a href=#122 id=122 data-nosnippet>122</a> }
<a href=#123 id=123 data-nosnippet>123</a>}
<a href=#124 id=124 data-nosnippet>124</a>
<a href=#125 id=125 data-nosnippet>125</a><span class="doccomment">/// Compares interned `Ref`s using pointer equality.
<a href=#126 id=126 data-nosnippet>126</a></span><span class="kw">impl</span>&lt;T: SliceInternable&gt; PartialEq <span class="kw">for </span>InternedSlice&lt;T&gt; {
<a href=#127 id=127 data-nosnippet>127</a> <span class="comment">// NOTE: No `?Sized` because `ptr_eq` doesn't work right with trait objects.
<a href=#128 id=128 data-nosnippet>128</a>
<a href=#129 id=129 data-nosnippet>129</a> </span><span class="attr">#[inline]
<a href=#130 id=130 data-nosnippet>130</a> </span><span class="kw">fn </span>eq(<span class="kw-2">&amp;</span><span class="self">self</span>, other: <span class="kw-2">&amp;</span><span class="self">Self</span>) -&gt; bool {
<a href=#131 id=131 data-nosnippet>131</a> <span class="self">self</span>.arc.as_ptr() == other.arc.as_ptr()
<a href=#132 id=132 data-nosnippet>132</a> }
<a href=#133 id=133 data-nosnippet>133</a>}
<a href=#134 id=134 data-nosnippet>134</a>
<a href=#135 id=135 data-nosnippet>135</a><span class="kw">impl</span>&lt;T: SliceInternable&gt; Eq <span class="kw">for </span>InternedSlice&lt;T&gt; {}
<a href=#136 id=136 data-nosnippet>136</a>
<a href=#137 id=137 data-nosnippet>137</a><span class="kw">impl</span>&lt;T: SliceInternable&gt; Hash <span class="kw">for </span>InternedSlice&lt;T&gt; {
<a href=#138 id=138 data-nosnippet>138</a> <span class="attr">#[inline]
<a href=#139 id=139 data-nosnippet>139</a> </span><span class="kw">fn </span>hash&lt;H: Hasher&gt;(<span class="kw-2">&amp;</span><span class="self">self</span>, state: <span class="kw-2">&amp;mut </span>H) {
<a href=#140 id=140 data-nosnippet>140</a> state.write_usize(<span class="self">self</span>.ptr().addr())
<a href=#141 id=141 data-nosnippet>141</a> }
<a href=#142 id=142 data-nosnippet>142</a>}
<a href=#143 id=143 data-nosnippet>143</a>
<a href=#144 id=144 data-nosnippet>144</a><span class="kw">impl</span>&lt;T: SliceInternable&gt; Deref <span class="kw">for </span>InternedSlice&lt;T&gt; {
<a href=#145 id=145 data-nosnippet>145</a> <span class="kw">type </span>Target = Pointee&lt;T&gt;;
<a href=#146 id=146 data-nosnippet>146</a>
<a href=#147 id=147 data-nosnippet>147</a> <span class="attr">#[inline]
<a href=#148 id=148 data-nosnippet>148</a> </span><span class="kw">fn </span>deref(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; <span class="kw-2">&amp;</span><span class="self">Self</span>::Target {
<a href=#149 id=149 data-nosnippet>149</a> <span class="kw-2">&amp;</span><span class="self">self</span>.arc
<a href=#150 id=150 data-nosnippet>150</a> }
<a href=#151 id=151 data-nosnippet>151</a>}
<a href=#152 id=152 data-nosnippet>152</a>
<a href=#153 id=153 data-nosnippet>153</a><span class="kw">impl</span>&lt;T: SliceInternable&gt; Clone <span class="kw">for </span>InternedSlice&lt;T&gt; {
<a href=#154 id=154 data-nosnippet>154</a> <span class="attr">#[inline]
<a href=#155 id=155 data-nosnippet>155</a> </span><span class="kw">fn </span>clone(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; <span class="self">Self </span>{
<a href=#156 id=156 data-nosnippet>156</a> <span class="self">Self </span>{ arc: <span class="self">self</span>.arc.clone() }
<a href=#157 id=157 data-nosnippet>157</a> }
<a href=#158 id=158 data-nosnippet>158</a>}
<a href=#159 id=159 data-nosnippet>159</a>
<a href=#160 id=160 data-nosnippet>160</a><span class="kw">impl</span>&lt;T&gt; Debug <span class="kw">for </span>InternedSlice&lt;T&gt;
<a href=#161 id=161 data-nosnippet>161</a><span class="kw">where
<a href=#162 id=162 data-nosnippet>162</a> </span>T: SliceInternable,
<a href=#163 id=163 data-nosnippet>163</a> T::SliceType: Debug,
<a href=#164 id=164 data-nosnippet>164</a> T::Header: Debug,
<a href=#165 id=165 data-nosnippet>165</a>{
<a href=#166 id=166 data-nosnippet>166</a> <span class="kw">fn </span>fmt(<span class="kw-2">&amp;</span><span class="self">self</span>, f: <span class="kw-2">&amp;mut </span>fmt::Formatter&lt;<span class="lifetime">'_</span>&gt;) -&gt; fmt::Result {
<a href=#167 id=167 data-nosnippet>167</a> (<span class="kw-2">*</span><span class="self">self</span>.arc).fmt(f)
<a href=#168 id=168 data-nosnippet>168</a> }
<a href=#169 id=169 data-nosnippet>169</a>}
<a href=#170 id=170 data-nosnippet>170</a>
<a href=#171 id=171 data-nosnippet>171</a><span class="attr">#[repr(transparent)]
<a href=#172 id=172 data-nosnippet>172</a></span><span class="kw">pub struct </span>InternedSliceRef&lt;<span class="lifetime">'a</span>, T&gt; {
<a href=#173 id=173 data-nosnippet>173</a> <span class="doccomment">/// # Invariant
<a href=#174 id=174 data-nosnippet>174</a> ///
<a href=#175 id=175 data-nosnippet>175</a> /// There is no `ThinArcBorrow` unfortunately, so this is basically a `ManuallyDrop&lt;ThinArc&gt;`,
<a href=#176 id=176 data-nosnippet>176</a> /// except that can't be `Copy`, so we store a raw pointer instead.
<a href=#177 id=177 data-nosnippet>177</a> </span>ptr: NonNull&lt;c_void&gt;,
<a href=#178 id=178 data-nosnippet>178</a> _marker: PhantomData&lt;<span class="kw-2">&amp;</span><span class="lifetime">'a </span>T&gt;,
<a href=#179 id=179 data-nosnippet>179</a>}
<a href=#180 id=180 data-nosnippet>180</a>
<a href=#181 id=181 data-nosnippet>181</a><span class="comment">// SAFETY: This is essentially a `ThinArc`, implemented as a raw pointer because there is no `ThinArcBorrowed`.
<a href=#182 id=182 data-nosnippet>182</a></span><span class="kw">unsafe impl</span>&lt;T: Send + Sync&gt; Send <span class="kw">for </span>InternedSliceRef&lt;<span class="lifetime">'_</span>, T&gt; {}
<a href=#183 id=183 data-nosnippet>183</a><span class="kw">unsafe impl</span>&lt;T: Send + Sync&gt; Sync <span class="kw">for </span>InternedSliceRef&lt;<span class="lifetime">'_</span>, T&gt; {}
<a href=#184 id=184 data-nosnippet>184</a>
<a href=#185 id=185 data-nosnippet>185</a><span class="kw">impl</span>&lt;<span class="lifetime">'a</span>, T: SliceInternable&gt; InternedSliceRef&lt;<span class="lifetime">'a</span>, T&gt; {
<a href=#186 id=186 data-nosnippet>186</a> <span class="attr">#[inline(always)]
<a href=#187 id=187 data-nosnippet>187</a> </span><span class="kw">fn </span>arc(<span class="self">self</span>) -&gt; ManuallyDrop&lt;ThinArc&lt;T::Header, T::SliceType&gt;&gt; {
<a href=#188 id=188 data-nosnippet>188</a> <span class="comment">// SAFETY: `self.ptr`'s invariant.
<a href=#189 id=189 data-nosnippet>189</a> </span><span class="kw">unsafe </span>{ ManuallyDrop::new(ThinArc::from_raw(<span class="self">self</span>.ptr.as_ptr())) }
<a href=#190 id=190 data-nosnippet>190</a> }
<a href=#191 id=191 data-nosnippet>191</a>
<a href=#192 id=192 data-nosnippet>192</a> <span class="attr">#[inline]
<a href=#193 id=193 data-nosnippet>193</a> </span><span class="kw">pub fn </span>to_owned(<span class="self">self</span>) -&gt; InternedSlice&lt;T&gt; {
<a href=#194 id=194 data-nosnippet>194</a> InternedSlice { arc: (<span class="kw-2">*</span><span class="self">self</span>.arc()).clone() }
<a href=#195 id=195 data-nosnippet>195</a> }
<a href=#196 id=196 data-nosnippet>196</a>
<a href=#197 id=197 data-nosnippet>197</a> <span class="attr">#[inline]
<a href=#198 id=198 data-nosnippet>198</a> </span><span class="kw">pub fn </span>get(<span class="self">self</span>) -&gt; <span class="kw-2">&amp;</span><span class="lifetime">'a </span>Pointee&lt;T&gt; {
<a href=#199 id=199 data-nosnippet>199</a> <span class="comment">// SAFETY: This is a lifetime extension, valid because we live for `'a`.
<a href=#200 id=200 data-nosnippet>200</a> </span><span class="kw">unsafe </span>{ <span class="kw-2">&amp;*</span>ptr::from_ref::&lt;Pointee&lt;T&gt;&gt;(<span class="kw-2">&amp;*</span><span class="self">self</span>.arc()) }
<a href=#201 id=201 data-nosnippet>201</a> }
<a href=#202 id=202 data-nosnippet>202</a>
<a href=#203 id=203 data-nosnippet>203</a> <span class="doccomment">/// # Safety
<a href=#204 id=204 data-nosnippet>204</a> ///
<a href=#205 id=205 data-nosnippet>205</a> /// You have to make sure the data is not referenced after the refcount reaches zero; beware the interning
<a href=#206 id=206 data-nosnippet>206</a> /// map also keeps a reference to the value.
<a href=#207 id=207 data-nosnippet>207</a> </span><span class="attr">#[inline]
<a href=#208 id=208 data-nosnippet>208</a> </span><span class="kw">pub unsafe fn </span>decrement_refcount(<span class="self">self</span>) {
<a href=#209 id=209 data-nosnippet>209</a> drop(ManuallyDrop::into_inner(<span class="self">self</span>.arc()));
<a href=#210 id=210 data-nosnippet>210</a> }
<a href=#211 id=211 data-nosnippet>211</a>
<a href=#212 id=212 data-nosnippet>212</a> <span class="attr">#[inline]
<a href=#213 id=213 data-nosnippet>213</a> </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>strong_count(<span class="self">self</span>) -&gt; usize {
<a href=#214 id=214 data-nosnippet>214</a> ThinArc::strong_count(<span class="kw-2">&amp;</span><span class="self">self</span>.arc())
<a href=#215 id=215 data-nosnippet>215</a> }
<a href=#216 id=216 data-nosnippet>216</a>
<a href=#217 id=217 data-nosnippet>217</a> <span class="attr">#[inline]
<a href=#218 id=218 data-nosnippet>218</a> </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>as_raw(<span class="self">self</span>) -&gt; <span class="kw-2">*const </span>c_void {
<a href=#219 id=219 data-nosnippet>219</a> <span class="self">self</span>.arc().as_ptr()
<a href=#220 id=220 data-nosnippet>220</a> }
<a href=#221 id=221 data-nosnippet>221</a>
<a href=#222 id=222 data-nosnippet>222</a> <span class="doccomment">/// **Available only on GC mode**.
<a href=#223 id=223 data-nosnippet>223</a> ///
<a href=#224 id=224 data-nosnippet>224</a> /// Changes the attached lifetime, as in GC mode, the lifetime is more kind of a lint to prevent misuse
<a href=#225 id=225 data-nosnippet>225</a> /// than actual soundness check.
<a href=#226 id=226 data-nosnippet>226</a> </span><span class="attr">#[inline]
<a href=#227 id=227 data-nosnippet>227</a> </span><span class="kw">pub fn </span>change_lifetime&lt;<span class="lifetime">'b</span>&gt;(<span class="self">self</span>) -&gt; InternedSliceRef&lt;<span class="lifetime">'b</span>, T&gt; {
<a href=#228 id=228 data-nosnippet>228</a> <span class="kw">const </span>{ <span class="macro">assert!</span>(T::USE_GC) };
<a href=#229 id=229 data-nosnippet>229</a> <span class="comment">// SAFETY: The lifetime on `InternedSliceRef` is essentially advisory only for GCed types.
<a href=#230 id=230 data-nosnippet>230</a> </span><span class="kw">unsafe </span>{ std::mem::transmute::&lt;InternedSliceRef&lt;<span class="lifetime">'a</span>, T&gt;, InternedSliceRef&lt;<span class="lifetime">'b</span>, T&gt;&gt;(<span class="self">self</span>) }
<a href=#231 id=231 data-nosnippet>231</a> }
<a href=#232 id=232 data-nosnippet>232</a>}
<a href=#233 id=233 data-nosnippet>233</a>
<a href=#234 id=234 data-nosnippet>234</a><span class="kw">impl</span>&lt;T&gt; Clone <span class="kw">for </span>InternedSliceRef&lt;<span class="lifetime">'_</span>, T&gt; {
<a href=#235 id=235 data-nosnippet>235</a> <span class="attr">#[inline]
<a href=#236 id=236 data-nosnippet>236</a> </span><span class="kw">fn </span>clone(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; <span class="self">Self </span>{
<a href=#237 id=237 data-nosnippet>237</a> <span class="kw-2">*</span><span class="self">self
<a href=#238 id=238 data-nosnippet>238</a> </span>}
<a href=#239 id=239 data-nosnippet>239</a>}
<a href=#240 id=240 data-nosnippet>240</a>
<a href=#241 id=241 data-nosnippet>241</a><span class="kw">impl</span>&lt;T&gt; Copy <span class="kw">for </span>InternedSliceRef&lt;<span class="lifetime">'_</span>, T&gt; {}
<a href=#242 id=242 data-nosnippet>242</a>
<a href=#243 id=243 data-nosnippet>243</a><span class="kw">impl</span>&lt;T: SliceInternable&gt; Hash <span class="kw">for </span>InternedSliceRef&lt;<span class="lifetime">'_</span>, T&gt; {
<a href=#244 id=244 data-nosnippet>244</a> <span class="attr">#[inline]
<a href=#245 id=245 data-nosnippet>245</a> </span><span class="kw">fn </span>hash&lt;H: Hasher&gt;(<span class="kw-2">&amp;</span><span class="self">self</span>, state: <span class="kw-2">&amp;mut </span>H) {
<a href=#246 id=246 data-nosnippet>246</a> state.write_usize(<span class="self">self</span>.ptr.as_ptr().addr());
<a href=#247 id=247 data-nosnippet>247</a> }
<a href=#248 id=248 data-nosnippet>248</a>}
<a href=#249 id=249 data-nosnippet>249</a>
<a href=#250 id=250 data-nosnippet>250</a><span class="kw">impl</span>&lt;T: SliceInternable&gt; PartialEq <span class="kw">for </span>InternedSliceRef&lt;<span class="lifetime">'_</span>, T&gt; {
<a href=#251 id=251 data-nosnippet>251</a> <span class="attr">#[inline]
<a href=#252 id=252 data-nosnippet>252</a> </span><span class="kw">fn </span>eq(<span class="kw-2">&amp;</span><span class="self">self</span>, other: <span class="kw-2">&amp;</span><span class="self">Self</span>) -&gt; bool {
<a href=#253 id=253 data-nosnippet>253</a> <span class="self">self</span>.ptr == other.ptr
<a href=#254 id=254 data-nosnippet>254</a> }
<a href=#255 id=255 data-nosnippet>255</a>}
<a href=#256 id=256 data-nosnippet>256</a>
<a href=#257 id=257 data-nosnippet>257</a><span class="kw">impl</span>&lt;T: SliceInternable&gt; Eq <span class="kw">for </span>InternedSliceRef&lt;<span class="lifetime">'_</span>, T&gt; {}
<a href=#258 id=258 data-nosnippet>258</a>
<a href=#259 id=259 data-nosnippet>259</a><span class="kw">impl</span>&lt;T: SliceInternable&gt; Deref <span class="kw">for </span>InternedSliceRef&lt;<span class="lifetime">'_</span>, T&gt; {
<a href=#260 id=260 data-nosnippet>260</a> <span class="kw">type </span>Target = Pointee&lt;T&gt;;
<a href=#261 id=261 data-nosnippet>261</a>
<a href=#262 id=262 data-nosnippet>262</a> <span class="attr">#[inline]
<a href=#263 id=263 data-nosnippet>263</a> </span><span class="kw">fn </span>deref(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; <span class="kw-2">&amp;</span><span class="self">Self</span>::Target {
<a href=#264 id=264 data-nosnippet>264</a> <span class="self">self</span>.get()
<a href=#265 id=265 data-nosnippet>265</a> }
<a href=#266 id=266 data-nosnippet>266</a>}
<a href=#267 id=267 data-nosnippet>267</a>
<a href=#268 id=268 data-nosnippet>268</a><span class="kw">impl</span>&lt;T&gt; Debug <span class="kw">for </span>InternedSliceRef&lt;<span class="lifetime">'_</span>, T&gt;
<a href=#269 id=269 data-nosnippet>269</a><span class="kw">where
<a href=#270 id=270 data-nosnippet>270</a> </span>T: SliceInternable,
<a href=#271 id=271 data-nosnippet>271</a> T::SliceType: Debug,
<a href=#272 id=272 data-nosnippet>272</a> T::Header: Debug,
<a href=#273 id=273 data-nosnippet>273</a>{
<a href=#274 id=274 data-nosnippet>274</a> <span class="kw">fn </span>fmt(<span class="kw-2">&amp;</span><span class="self">self</span>, f: <span class="kw-2">&amp;mut </span>fmt::Formatter&lt;<span class="lifetime">'_</span>&gt;) -&gt; fmt::Result {
<a href=#275 id=275 data-nosnippet>275</a> (<span class="kw-2">**</span><span class="self">self</span>).fmt(f)
<a href=#276 id=276 data-nosnippet>276</a> }
<a href=#277 id=277 data-nosnippet>277</a>}
<a href=#278 id=278 data-nosnippet>278</a>
<a href=#279 id=279 data-nosnippet>279</a><span class="kw">pub struct </span>InternSliceStorage&lt;T: SliceInternable&gt; {
<a href=#280 id=280 data-nosnippet>280</a> map: OnceLock&lt;InternMap&lt;T&gt;&gt;,
<a href=#281 id=281 data-nosnippet>281</a>}
<a href=#282 id=282 data-nosnippet>282</a>
<a href=#283 id=283 data-nosnippet>283</a><span class="attr">#[allow(
<a href=#284 id=284 data-nosnippet>284</a> clippy::new_without_default,
<a href=#285 id=285 data-nosnippet>285</a> reason = <span class="string">"this a const fn, so it can't be default yet. See &lt;https://github.com/rust-lang/rust/issues/63065&gt;"
<a href=#286 id=286 data-nosnippet>286</a></span>)]
<a href=#287 id=287 data-nosnippet>287</a></span><span class="kw">impl</span>&lt;T: SliceInternable&gt; InternSliceStorage&lt;T&gt; {
<a href=#288 id=288 data-nosnippet>288</a> <span class="kw">pub const fn </span>new() -&gt; <span class="self">Self </span>{
<a href=#289 id=289 data-nosnippet>289</a> <span class="self">Self </span>{ map: OnceLock::new() }
<a href=#290 id=290 data-nosnippet>290</a> }
<a href=#291 id=291 data-nosnippet>291</a>}
<a href=#292 id=292 data-nosnippet>292</a>
<a href=#293 id=293 data-nosnippet>293</a><span class="kw">impl</span>&lt;T: SliceInternable&gt; InternSliceStorage&lt;T&gt; {
<a href=#294 id=294 data-nosnippet>294</a> <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>get(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; <span class="kw-2">&amp;</span>InternMap&lt;T&gt; {
<a href=#295 id=295 data-nosnippet>295</a> <span class="self">self</span>.map.get_or_init(|| {
<a href=#296 id=296 data-nosnippet>296</a> DashMap::with_capacity_and_hasher(
<a href=#297 id=297 data-nosnippet>297</a> (<span class="number">64 </span>* <span class="number">1024</span>) / std::mem::size_of::&lt;T::SliceType&gt;(),
<a href=#298 id=298 data-nosnippet>298</a> Default::default(),
<a href=#299 id=299 data-nosnippet>299</a> )
<a href=#300 id=300 data-nosnippet>300</a> })
<a href=#301 id=301 data-nosnippet>301</a> }
<a href=#302 id=302 data-nosnippet>302</a>}
<a href=#303 id=303 data-nosnippet>303</a>
<a href=#304 id=304 data-nosnippet>304</a><span class="kw">pub trait </span>SliceInternable: Sized + <span class="lifetime">'static </span>{
<a href=#305 id=305 data-nosnippet>305</a> <span class="kw">const </span>USE_GC: bool;
<a href=#306 id=306 data-nosnippet>306</a> <span class="kw">type </span>Header: Eq + Hash + Send + Sync;
<a href=#307 id=307 data-nosnippet>307</a> <span class="kw">type </span>SliceType: Eq + Hash + Send + Sync + Copy + <span class="lifetime">'static</span>;
<a href=#308 id=308 data-nosnippet>308</a> <span class="kw">fn </span>storage() -&gt; <span class="kw-2">&amp;</span><span class="lifetime">'static </span>InternSliceStorage&lt;<span class="self">Self</span>&gt;;
<a href=#309 id=309 data-nosnippet>309</a>}
<a href=#310 id=310 data-nosnippet>310</a>
<a href=#311 id=311 data-nosnippet>311</a><span class="doccomment">/// Implements `SliceInternable` for a given list of types, making them usable with `InternedSlice`.
<a href=#312 id=312 data-nosnippet>312</a></span><span class="attr">#[macro_export]
<a href=#313 id=313 data-nosnippet>313</a>#[doc(hidden)]
<a href=#314 id=314 data-nosnippet>314</a></span><span class="macro">macro_rules!</span> _impl_slice_internable {
<a href=#315 id=315 data-nosnippet>315</a> ( gc; <span class="macro-nonterminal">$tag</span>:ident, <span class="macro-nonterminal">$h</span>:ty, <span class="macro-nonterminal">$t</span>:ty $(,)<span class="question-mark">? </span>) =&gt; {
<a href=#316 id=316 data-nosnippet>316</a> <span class="attr">#[allow(unreachable_pub)]
<a href=#317 id=317 data-nosnippet>317</a> </span><span class="kw">pub struct </span><span class="macro-nonterminal">$tag</span>;
<a href=#318 id=318 data-nosnippet>318</a> <span class="kw">impl </span><span class="macro-nonterminal">$crate::SliceInternable </span><span class="kw">for </span><span class="macro-nonterminal">$tag </span>{
<a href=#319 id=319 data-nosnippet>319</a> <span class="kw">const </span>USE_GC: bool = <span class="bool-val">true</span>;
<a href=#320 id=320 data-nosnippet>320</a> <span class="kw">type </span>Header = <span class="macro-nonterminal">$h</span>;
<a href=#321 id=321 data-nosnippet>321</a> <span class="kw">type </span>SliceType = <span class="macro-nonterminal">$t</span>;
<a href=#322 id=322 data-nosnippet>322</a> <span class="kw">fn </span>storage() -&gt; <span class="kw-2">&amp;</span><span class="lifetime">'static </span><span class="macro-nonterminal">$crate::InternSliceStorage</span>&lt;<span class="self">Self</span>&gt; {
<a href=#323 id=323 data-nosnippet>323</a> <span class="kw">static </span>STORAGE: <span class="macro-nonterminal">$crate::InternSliceStorage</span>&lt;<span class="macro-nonterminal">$tag</span>&gt; =
<a href=#324 id=324 data-nosnippet>324</a> <span class="macro-nonterminal">$crate::InternSliceStorage::new</span>();
<a href=#325 id=325 data-nosnippet>325</a> <span class="kw-2">&amp;</span>STORAGE
<a href=#326 id=326 data-nosnippet>326</a> }
<a href=#327 id=327 data-nosnippet>327</a> }
<a href=#328 id=328 data-nosnippet>328</a> };
<a href=#329 id=329 data-nosnippet>329</a>}
<a href=#330 id=330 data-nosnippet>330</a><span class="kw">pub use </span><span class="kw">crate</span>::_impl_slice_internable <span class="kw">as </span>impl_slice_internable;
</code></pre></div></section></main></body></html>