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| 22 | <a href="./Home">MLton 20180207</a>\r |
| 23 | </div>\r |
| 24 | </div>\r |
| 25 | <div id="header">\r |
| 26 | <h1>Elaborate</h1>\r |
| 27 | </div>\r |
| 28 | <div id="content">\r |
| 29 | <div id="preamble">\r |
| 30 | <div class="sectionbody">\r |
| 31 | <div class="paragraph"><p><a href="Elaborate">Elaborate</a> is a translation pass from the <a href="AST">AST</a>\r |
| 32 | <a href="IntermediateLanguage">IntermediateLanguage</a> to the <a href="CoreML">CoreML</a> <a href="IntermediateLanguage">IntermediateLanguage</a>.</p></div>\r |
| 33 | </div>\r |
| 34 | </div>\r |
| 35 | <div class="sect1">\r |
| 36 | <h2 id="_description">Description</h2>\r |
| 37 | <div class="sectionbody">\r |
| 38 | <div class="paragraph"><p>This pass performs type inference and type checking according to the\r |
| 39 | <a href="DefinitionOfStandardML">Definition</a>. It also defunctorizes the\r |
| 40 | program, eliminating all module-level constructs.</p></div>\r |
| 41 | </div>\r |
| 42 | </div>\r |
| 43 | <div class="sect1">\r |
| 44 | <h2 id="_implementation">Implementation</h2>\r |
| 45 | <div class="sectionbody">\r |
| 46 | <div class="ulist"><ul>\r |
| 47 | <li>\r |
| 48 | <p>\r |
| 49 | <a href="https://github.com/MLton/mlton/blob/master/mlton/elaborate/elaborate.sig"><span class="monospaced">elaborate.sig</span></a>\r |
| 50 | </p>\r |
| 51 | </li>\r |
| 52 | <li>\r |
| 53 | <p>\r |
| 54 | <a href="https://github.com/MLton/mlton/blob/master/mlton/elaborate/elaborate.fun"><span class="monospaced">elaborate.fun</span></a>\r |
| 55 | </p>\r |
| 56 | </li>\r |
| 57 | <li>\r |
| 58 | <p>\r |
| 59 | <a href="https://github.com/MLton/mlton/blob/master/mlton/elaborate/elaborate-env.sig"><span class="monospaced">elaborate-env.sig</span></a>\r |
| 60 | </p>\r |
| 61 | </li>\r |
| 62 | <li>\r |
| 63 | <p>\r |
| 64 | <a href="https://github.com/MLton/mlton/blob/master/mlton/elaborate/elaborate-env.fun"><span class="monospaced">elaborate-env.fun</span></a>\r |
| 65 | </p>\r |
| 66 | </li>\r |
| 67 | <li>\r |
| 68 | <p>\r |
| 69 | <a href="https://github.com/MLton/mlton/blob/master/mlton/elaborate/elaborate-modules.sig"><span class="monospaced">elaborate-modules.sig</span></a>\r |
| 70 | </p>\r |
| 71 | </li>\r |
| 72 | <li>\r |
| 73 | <p>\r |
| 74 | <a href="https://github.com/MLton/mlton/blob/master/mlton/elaborate/elaborate-modules.fun"><span class="monospaced">elaborate-modules.fun</span></a>\r |
| 75 | </p>\r |
| 76 | </li>\r |
| 77 | <li>\r |
| 78 | <p>\r |
| 79 | <a href="https://github.com/MLton/mlton/blob/master/mlton/elaborate/elaborate-core.sig"><span class="monospaced">elaborate-core.sig</span></a>\r |
| 80 | </p>\r |
| 81 | </li>\r |
| 82 | <li>\r |
| 83 | <p>\r |
| 84 | <a href="https://github.com/MLton/mlton/blob/master/mlton/elaborate/elaborate-core.fun"><span class="monospaced">elaborate-core.fun</span></a>\r |
| 85 | </p>\r |
| 86 | </li>\r |
| 87 | <li>\r |
| 88 | <p>\r |
| 89 | <a href="https://github.com/MLton/mlton/tree/master/mlton/elaborate"><span class="monospaced">elaborate</span></a>\r |
| 90 | </p>\r |
| 91 | </li>\r |
| 92 | </ul></div>\r |
| 93 | </div>\r |
| 94 | </div>\r |
| 95 | <div class="sect1">\r |
| 96 | <h2 id="_details_and_notes">Details and Notes</h2>\r |
| 97 | <div class="sectionbody">\r |
| 98 | <div class="paragraph"><p>At the modules level, the <a href="Elaborate">Elaborate</a> pass:</p></div>\r |
| 99 | <div class="ulist"><ul>\r |
| 100 | <li>\r |
| 101 | <p>\r |
| 102 | elaborates signatures with interfaces (see\r |
| 103 | <a href="https://github.com/MLton/mlton/blob/master/mlton/elaborate/interface.sig"><span class="monospaced">interface.sig</span></a> and\r |
| 104 | <a href="https://github.com/MLton/mlton/blob/master/mlton/elaborate/interface.fun"><span class="monospaced">interface.fun</span></a>)\r |
| 105 | </p>\r |
| 106 | <div class="paragraph"><p>The main trick is to use disjoint sets to efficiently handle sharing\r |
| 107 | of tycons and of structures and then to copy signatures as dags rather\r |
| 108 | than as trees.</p></div>\r |
| 109 | </li>\r |
| 110 | <li>\r |
| 111 | <p>\r |
| 112 | checks functors at the point of definition, using functor summaries\r |
| 113 | to speed up checking of functor applications.\r |
| 114 | </p>\r |
| 115 | <div class="paragraph"><p>When a functor is first type checked, we keep track of the dummy\r |
| 116 | argument structure and the dummy result structure, as well as all the\r |
| 117 | tycons that were created while elaborating the body. Then, if we\r |
| 118 | later need to type check an application of the functor (as opposed to\r |
| 119 | defunctorize an application), we pair up tycons in the dummy argument\r |
| 120 | structure with the actual argument structure and then replace the\r |
| 121 | dummy tycons with the actual tycons in the dummy result structure,\r |
| 122 | yielding the actual result structure. We also generate new tycons for\r |
| 123 | all the tycons that we created while originally elaborating the body.</p></div>\r |
| 124 | </li>\r |
| 125 | <li>\r |
| 126 | <p>\r |
| 127 | handles opaque signature constraints.\r |
| 128 | </p>\r |
| 129 | <div class="paragraph"><p>This is implemented by building a dummy structure realized from the\r |
| 130 | signature, just as we would for a functor argument when type checking\r |
| 131 | a functor. The dummy structure contains exactly the type information\r |
| 132 | that is in the signature, which is what opacity requires. We then\r |
| 133 | replace the variables (and constructors) in the dummy structure with\r |
| 134 | the corresponding variables (and constructors) from the actual\r |
| 135 | structure so that the translation to <a href="CoreML">CoreML</a> uses the right stuff.\r |
| 136 | For each tycon in the dummy structure, we keep track of the\r |
| 137 | corresponding type structure in the actual structure. This is used\r |
| 138 | when producing the <a href="CoreML">CoreML</a> types (see <span class="monospaced">expandOpaque</span> in\r |
| 139 | <a href="https://github.com/MLton/mlton/blob/master/mlton/elaborate/type-env.sig"><span class="monospaced">type-env.sig</span></a> and\r |
| 140 | <a href="https://github.com/MLton/mlton/blob/master/mlton/elaborate/type-env.fun"><span class="monospaced">type-env.fun</span></a>).</p></div>\r |
| 141 | <div class="paragraph"><p>Then, within each <span class="monospaced">structure</span> or <span class="monospaced">functor</span> body, for each declaration\r |
| 142 | (<span class="monospaced"><dec></span> in the <a href="StandardML">Standard ML</a> grammar), the <a href="Elaborate">Elaborate</a>\r |
| 143 | pass does three steps:</p></div>\r |
| 144 | <div class="openblock">\r |
| 145 | <div class="content">\r |
| 146 | <div class="olist arabic"><ol class="arabic">\r |
| 147 | <li>\r |
| 148 | <p>\r |
| 149 | <a href="ScopeInference">ScopeInference</a>\r |
| 150 | </p>\r |
| 151 | </li>\r |
| 152 | <li>\r |
| 153 | <p>\r |
| 154 | </p>\r |
| 155 | <div class="ulist"><ul>\r |
| 156 | <li>\r |
| 157 | <p>\r |
| 158 | <a href="PrecedenceParse">PrecedenceParse</a>\r |
| 159 | </p>\r |
| 160 | </li>\r |
| 161 | <li>\r |
| 162 | <p>\r |
| 163 | <span class="monospaced">_{ex,im}port</span> expansion\r |
| 164 | </p>\r |
| 165 | </li>\r |
| 166 | <li>\r |
| 167 | <p>\r |
| 168 | profiling insertion\r |
| 169 | </p>\r |
| 170 | </li>\r |
| 171 | <li>\r |
| 172 | <p>\r |
| 173 | unification\r |
| 174 | </p>\r |
| 175 | </li>\r |
| 176 | </ul></div>\r |
| 177 | </li>\r |
| 178 | <li>\r |
| 179 | <p>\r |
| 180 | Overloaded {constant, function, record pattern} resolution\r |
| 181 | </p>\r |
| 182 | </li>\r |
| 183 | </ol></div>\r |
| 184 | </div></div>\r |
| 185 | </li>\r |
| 186 | </ul></div>\r |
| 187 | <div class="sect2">\r |
| 188 | <h3 id="_defunctorization">Defunctorization</h3>\r |
| 189 | <div class="paragraph"><p>The <a href="Elaborate">Elaborate</a> pass performs a number of duties historically\r |
| 190 | assigned to the <a href="Defunctorize">Defunctorize</a> pass.</p></div>\r |
| 191 | <div class="paragraph"><p>As part of the <a href="Elaborate">Elaborate</a> pass, all module level constructs\r |
| 192 | (<span class="monospaced">open</span>, <span class="monospaced">signature</span>, <span class="monospaced">structure</span>, <span class="monospaced">functor</span>, long identifiers) are\r |
| 193 | removed. This works because the <a href="Elaborate">Elaborate</a> pass assigns a unique\r |
| 194 | name to every type and variable in the program. This also allows the\r |
| 195 | <a href="Elaborate">Elaborate</a> pass to eliminate <span class="monospaced">local</span> declarations, which are purely\r |
| 196 | for namespace management.</p></div>\r |
| 197 | </div>\r |
| 198 | </div>\r |
| 199 | </div>\r |
| 200 | <div class="sect1">\r |
| 201 | <h2 id="_examples">Examples</h2>\r |
| 202 | <div class="sectionbody">\r |
| 203 | <div class="paragraph"><p>Here are a number of examples of elaboration.</p></div>\r |
| 204 | <div class="ulist"><ul>\r |
| 205 | <li>\r |
| 206 | <p>\r |
| 207 | All variables bound in <span class="monospaced">val</span> declarations are renamed.\r |
| 208 | </p>\r |
| 209 | <div class="listingblock">\r |
| 210 | <div class="content"><div class="highlight"><pre><span class="k">val</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="mi">13</span><span class="w"></span>\r |
| 211 | <span class="k">val</span><span class="w"> </span><span class="n">y</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">x</span><span class="w"></span>\r |
| 212 | </pre></div></div></div>\r |
| 213 | <div class="listingblock">\r |
| 214 | <div class="content monospaced">\r |
| 215 | <pre>val x_0 = 13\r |
| 216 | val y_0 = x_0</pre>\r |
| 217 | </div></div>\r |
| 218 | </li>\r |
| 219 | <li>\r |
| 220 | <p>\r |
| 221 | All variables in <span class="monospaced">fun</span> declarations are renamed.\r |
| 222 | </p>\r |
| 223 | <div class="listingblock">\r |
| 224 | <div class="content"><div class="highlight"><pre><span class="k">fun</span><span class="w"> </span><span class="n">f</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">g</span><span class="w"> </span><span class="n">x</span><span class="w"></span>\r |
| 225 | <span class="k">and</span><span class="w"> </span><span class="n">g</span><span class="w"> </span><span class="n">y</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">f</span><span class="w"> </span><span class="n">y</span><span class="w"></span>\r |
| 226 | </pre></div></div></div>\r |
| 227 | <div class="listingblock">\r |
| 228 | <div class="content monospaced">\r |
| 229 | <pre>fun f_0 x_0 = g_0 x_0\r |
| 230 | and g_0 y_0 = f_0 y_0</pre>\r |
| 231 | </div></div>\r |
| 232 | </li>\r |
| 233 | <li>\r |
| 234 | <p>\r |
| 235 | Type abbreviations are removed, and the abbreviation is expanded\r |
| 236 | wherever it is used.\r |
| 237 | </p>\r |
| 238 | <div class="listingblock">\r |
| 239 | <div class="content"><div class="highlight"><pre><span class="k">type</span><span class="w"> </span><span class="n">'a</span><span class="w"> </span><span class="n">u</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">int</span><span class="w"> </span><span class="n">*</span><span class="w"> </span><span class="n">'a</span><span class="w"></span>\r |
| 240 | <span class="k">type</span><span class="w"> </span><span class="n">'b</span><span class="w"> </span><span class="n">t</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">'b</span><span class="w"> </span><span class="n">u</span><span class="w"> </span><span class="n">*</span><span class="w"> </span><span class="n">real</span><span class="w"></span>\r |
| 241 | <span class="k">fun</span><span class="w"> </span><span class="n">f</span><span class="w"> </span><span class="p">(</span><span class="n">x</span><span class="w"> </span><span class="p">:</span><span class="w"> </span><span class="n">bool</span><span class="w"> </span><span class="n">t</span><span class="p">)</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">x</span><span class="w"></span>\r |
| 242 | </pre></div></div></div>\r |
| 243 | <div class="listingblock">\r |
| 244 | <div class="content monospaced">\r |
| 245 | <pre>fun f_0 (x_0 : (int * bool) * real) = x_0</pre>\r |
| 246 | </div></div>\r |
| 247 | </li>\r |
| 248 | <li>\r |
| 249 | <p>\r |
| 250 | Exception declarations create a new constructor and rename the type.\r |
| 251 | </p>\r |
| 252 | <div class="listingblock">\r |
| 253 | <div class="content"><div class="highlight"><pre><span class="k">type</span><span class="w"> </span><span class="n">t</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">int</span><span class="w"></span>\r |
| 254 | <span class="k">exception</span><span class="w"> </span><span class="n">E</span><span class="w"> </span><span class="k">of</span><span class="w"> </span><span class="n">t</span><span class="w"> </span><span class="n">*</span><span class="w"> </span><span class="n">real</span><span class="w"></span>\r |
| 255 | </pre></div></div></div>\r |
| 256 | <div class="listingblock">\r |
| 257 | <div class="content monospaced">\r |
| 258 | <pre>exception E_0 of int * real</pre>\r |
| 259 | </div></div>\r |
| 260 | </li>\r |
| 261 | <li>\r |
| 262 | <p>\r |
| 263 | The type and value constructors in datatype declarations are renamed.\r |
| 264 | </p>\r |
| 265 | <div class="listingblock">\r |
| 266 | <div class="content"><div class="highlight"><pre><span class="k">datatype</span><span class="w"> </span><span class="n">t</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">A</span><span class="w"> </span><span class="k">of</span><span class="w"> </span><span class="n">int</span><span class="w"> </span><span class="p">|</span><span class="w"> </span><span class="n">B</span><span class="w"> </span><span class="k">of</span><span class="w"> </span><span class="n">real</span><span class="w"> </span><span class="n">*</span><span class="w"> </span><span class="n">t</span><span class="w"></span>\r |
| 267 | </pre></div></div></div>\r |
| 268 | <div class="listingblock">\r |
| 269 | <div class="content monospaced">\r |
| 270 | <pre>datatype t_0 = A_0 of int | B_0 of real * t_0</pre>\r |
| 271 | </div></div>\r |
| 272 | </li>\r |
| 273 | <li>\r |
| 274 | <p>\r |
| 275 | Local declarations are moved to the top-level. The environment\r |
| 276 | keeps track of the variables in scope.\r |
| 277 | </p>\r |
| 278 | <div class="listingblock">\r |
| 279 | <div class="content"><div class="highlight"><pre><span class="k">val</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="mi">13</span><span class="w"></span>\r |
| 280 | <span class="k">local</span><span class="w"> </span><span class="k">val</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="mi">14</span><span class="w"></span>\r |
| 281 | <span class="k">in</span><span class="w"> </span><span class="k">val</span><span class="w"> </span><span class="n">y</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">x</span><span class="w"></span>\r |
| 282 | <span class="k">end</span><span class="w"></span>\r |
| 283 | <span class="k">val</span><span class="w"> </span><span class="n">z</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">x</span><span class="w"></span>\r |
| 284 | </pre></div></div></div>\r |
| 285 | <div class="listingblock">\r |
| 286 | <div class="content monospaced">\r |
| 287 | <pre>val x_0 = 13\r |
| 288 | val x_1 = 14\r |
| 289 | val y_0 = x_1\r |
| 290 | val z_0 = x_0</pre>\r |
| 291 | </div></div>\r |
| 292 | </li>\r |
| 293 | <li>\r |
| 294 | <p>\r |
| 295 | Structure declarations are eliminated, with all declarations moved\r |
| 296 | to the top level. Long identifiers are renamed.\r |
| 297 | </p>\r |
| 298 | <div class="listingblock">\r |
| 299 | <div class="content"><div class="highlight"><pre><span class="k">structure</span><span class="w"> </span><span class="n">S</span><span class="w"> </span><span class="p">=</span><span class="w"></span>\r |
| 300 | <span class="w"> </span><span class="k">struct</span><span class="w"></span>\r |
| 301 | <span class="w"> </span><span class="k">type</span><span class="w"> </span><span class="n">t</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">int</span><span class="w"></span>\r |
| 302 | <span class="w"> </span><span class="k">val</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="p">:</span><span class="w"> </span><span class="n">t</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="mi">13</span><span class="w"></span>\r |
| 303 | <span class="w"> </span><span class="k">end</span><span class="w"></span>\r |
| 304 | <span class="k">val</span><span class="w"> </span><span class="n">y</span><span class="w"> </span><span class="p">:</span><span class="w"> </span><span class="n">S</span><span class="p">.</span><span class="n">t</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">S</span><span class="p">.</span><span class="n">x</span><span class="w"></span>\r |
| 305 | </pre></div></div></div>\r |
| 306 | <div class="listingblock">\r |
| 307 | <div class="content monospaced">\r |
| 308 | <pre>val x_0 : int = 13\r |
| 309 | val y_0 : int = x_0</pre>\r |
| 310 | </div></div>\r |
| 311 | </li>\r |
| 312 | <li>\r |
| 313 | <p>\r |
| 314 | Open declarations are eliminated.\r |
| 315 | </p>\r |
| 316 | <div class="listingblock">\r |
| 317 | <div class="content"><div class="highlight"><pre><span class="k">val</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="mi">13</span><span class="w"></span>\r |
| 318 | <span class="k">val</span><span class="w"> </span><span class="n">y</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="mi">14</span><span class="w"></span>\r |
| 319 | <span class="k">structure</span><span class="w"> </span><span class="n">S</span><span class="w"> </span><span class="p">=</span><span class="w"></span>\r |
| 320 | <span class="w"> </span><span class="k">struct</span><span class="w"></span>\r |
| 321 | <span class="w"> </span><span class="k">val</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="mi">15</span><span class="w"></span>\r |
| 322 | <span class="w"> </span><span class="k">end</span><span class="w"></span>\r |
| 323 | <span class="k">open</span><span class="w"> </span><span class="n">S</span><span class="w"></span>\r |
| 324 | <span class="k">val</span><span class="w"> </span><span class="n">z</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="n">+</span><span class="w"> </span><span class="n">y</span><span class="w"></span>\r |
| 325 | </pre></div></div></div>\r |
| 326 | <div class="listingblock">\r |
| 327 | <div class="content monospaced">\r |
| 328 | <pre>val x_0 = 13\r |
| 329 | val y_0 = 14\r |
| 330 | val x_1 = 15\r |
| 331 | val z_0 = x_1 + y_0</pre>\r |
| 332 | </div></div>\r |
| 333 | </li>\r |
| 334 | <li>\r |
| 335 | <p>\r |
| 336 | Functor declarations are eliminated, and the body of a functor is\r |
| 337 | duplicated wherever the functor is applied.\r |
| 338 | </p>\r |
| 339 | <div class="listingblock">\r |
| 340 | <div class="content"><div class="highlight"><pre><span class="k">functor</span><span class="w"> </span><span class="n">F</span><span class="p">(</span><span class="k">val</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="p">:</span><span class="w"> </span><span class="n">int</span><span class="p">)</span><span class="w"> </span><span class="p">=</span><span class="w"></span>\r |
| 341 | <span class="w"> </span><span class="k">struct</span><span class="w"></span>\r |
| 342 | <span class="w"> </span><span class="k">val</span><span class="w"> </span><span class="n">y</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">x</span><span class="w"></span>\r |
| 343 | <span class="w"> </span><span class="k">end</span><span class="w"></span>\r |
| 344 | <span class="k">structure</span><span class="w"> </span><span class="n">F1</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">F</span><span class="p">(</span><span class="k">val</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="mi">13</span><span class="p">)</span><span class="w"></span>\r |
| 345 | <span class="k">structure</span><span class="w"> </span><span class="n">F2</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">F</span><span class="p">(</span><span class="k">val</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="mi">14</span><span class="p">)</span><span class="w"></span>\r |
| 346 | <span class="k">val</span><span class="w"> </span><span class="n">z</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">F1</span><span class="p">.</span><span class="n">y</span><span class="w"> </span><span class="n">+</span><span class="w"> </span><span class="n">F2</span><span class="p">.</span><span class="n">y</span><span class="w"></span>\r |
| 347 | </pre></div></div></div>\r |
| 348 | <div class="listingblock">\r |
| 349 | <div class="content monospaced">\r |
| 350 | <pre>val x_0 = 13\r |
| 351 | val y_0 = x_0\r |
| 352 | val x_1 = 14\r |
| 353 | val y_1 = x_1\r |
| 354 | val z_0 = y_0 + y_1</pre>\r |
| 355 | </div></div>\r |
| 356 | </li>\r |
| 357 | <li>\r |
| 358 | <p>\r |
| 359 | Signature constraints are eliminated. Note that signatures do\r |
| 360 | affect how subsequent variables are renamed.\r |
| 361 | </p>\r |
| 362 | <div class="listingblock">\r |
| 363 | <div class="content"><div class="highlight"><pre><span class="k">val</span><span class="w"> </span><span class="n">y</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="mi">13</span><span class="w"></span>\r |
| 364 | <span class="k">structure</span><span class="w"> </span><span class="n">S</span><span class="w"> </span><span class="p">:</span><span class="w"> </span><span class="k">sig</span><span class="w"></span>\r |
| 365 | <span class="w"> </span><span class="k">val</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="p">:</span><span class="w"> </span><span class="n">int</span><span class="w"></span>\r |
| 366 | <span class="w"> </span><span class="k">end</span><span class="w"> </span><span class="p">=</span><span class="w"></span>\r |
| 367 | <span class="w"> </span><span class="k">struct</span><span class="w"></span>\r |
| 368 | <span class="w"> </span><span class="k">val</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="mi">14</span><span class="w"></span>\r |
| 369 | <span class="w"> </span><span class="k">val</span><span class="w"> </span><span class="n">y</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">x</span><span class="w"></span>\r |
| 370 | <span class="w"> </span><span class="k">end</span><span class="w"></span>\r |
| 371 | <span class="k">open</span><span class="w"> </span><span class="n">S</span><span class="w"></span>\r |
| 372 | <span class="k">val</span><span class="w"> </span><span class="n">z</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="n">+</span><span class="w"> </span><span class="n">y</span><span class="w"></span>\r |
| 373 | </pre></div></div></div>\r |
| 374 | <div class="listingblock">\r |
| 375 | <div class="content monospaced">\r |
| 376 | <pre>val y_0 = 13\r |
| 377 | val x_0 = 14\r |
| 378 | val y_1 = x_0\r |
| 379 | val z_0 = x_0 + y_0</pre>\r |
| 380 | </div></div>\r |
| 381 | </li>\r |
| 382 | </ul></div>\r |
| 383 | </div>\r |
| 384 | </div>\r |
| 385 | </div>\r |
| 386 | <div id="footnotes"><hr></div>\r |
| 387 | <div id="footer">\r |
| 388 | <div id="footer-text">\r |
| 389 | </div>\r |
| 390 | <div id="footer-badges">\r |
| 391 | </div>\r |
| 392 | </div>\r |
| 393 | </body>\r |
| 394 | </html>\r |