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19 | <body class="article">\r | |
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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 |