doc/guide/localhost/Utilities

   1 <!DOCTYPE html>
   2 <html lang="en">
   3 <head>
   4 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
   5 <meta name="generator" content="AsciiDoc 8.6.9">
   6 <title>Utilities</title>
   7 <link rel="stylesheet" href="./asciidoc.css" type="text/css">
   8 <link rel="stylesheet" href="./pygments.css" type="text/css">
   9
  10
  11 <script type="text/javascript" src="./asciidoc.js"></script>
  12 <script type="text/javascript">
  13 /*<![CDATA[*/
  14 asciidoc.install();
  15 /*]]>*/
  16 </script>
  17 <link rel="stylesheet" href="./mlton.css" type="text/css">
  18 </head>
  19 <body class="article">
  20 <div id="banner">
  21 <div id="banner-home">
  22 <a href="./Home">MLton 20180207</a>
  23 </div>
  24 </div>
  25 <div id="header">
  26 <h1>Utilities</h1>
  27 </div>
  28 <div id="content">
  29 <div id="preamble">
  30 <div class="sectionbody">
  31 <div class="paragraph"><p>This page is a collection of basic utilities used in the examples on
  32 various pages.  See</p></div>
  33 <div class="ulist"><ul>
  34 <li>
  35 <p>
  36 <a href="InfixingOperators">InfixingOperators</a>, and
  37 </p>
  38 </li>
  39 <li>
  40 <p>
  41 <a href="ProductType">ProductType</a>
  42 </p>
  43 </li>
  44 </ul></div>
  45 <div class="paragraph"><p>for longer discussions on some of these utilities.</p></div>
  46 <div class="listingblock">
  47 <div class="content"><div class="highlight"><pre><span class="cm">(* Operator precedence table *)</span><span class="w"></span>
  48 <span class="k">infix</span><span class="w">   </span><span class="mi">8</span><span class="w">  </span><span class="n">*</span><span class="w"> </span><span class="n">/</span><span class="w"> </span><span class="n">div</span><span class="w"> </span><span class="n">mod</span><span class="w">        </span><span class="cm">(* +1 from Basis Library *)</span><span class="w"></span>
  49 <span class="k">infix</span><span class="w">   </span><span class="mi">7</span><span class="w">  </span><span class="n">+</span><span class="w"> </span><span class="n">-</span><span class="w"> </span><span class="n">^</span><span class="w">              </span><span class="cm">(* +1 from Basis Library *)</span><span class="w"></span>
  50 <span class="k">infixr</span><span class="w">  </span><span class="mi">6</span><span class="w">  </span><span class="n">::</span><span class="w"> </span><span class="n">@</span><span class="w">               </span><span class="cm">(* +1 from Basis Library *)</span><span class="w"></span>
  51 <span class="k">infix</span><span class="w">   </span><span class="mi">5</span><span class="w">  </span><span class="p">=</span><span class="w"> </span><span class="n">&lt;&gt;</span><span class="w"> </span><span class="n">&gt;</span><span class="w"> </span><span class="n">&gt;=</span><span class="w"> </span><span class="n">&lt;</span><span class="w"> </span><span class="n">&lt;=</span><span class="w">     </span><span class="cm">(* +1 from Basis Library *)</span><span class="w"></span>
  52 <span class="k">infix</span><span class="w">   </span><span class="mi">4</span><span class="w">  </span><span class="n">&lt;\</span><span class="w"> </span><span class="n">\&gt;</span><span class="w"></span>
  53 <span class="k">infixr</span><span class="w">  </span><span class="mi">4</span><span class="w">  </span><span class="n">&lt;/</span><span class="w"> </span><span class="n">/&gt;</span><span class="w"></span>
  54 <span class="k">infix</span><span class="w">   </span><span class="mi">3</span><span class="w">  </span><span class="n">o</span><span class="w"></span>
  55 <span class="k">infix</span><span class="w">   </span><span class="mi">2</span><span class="w">  </span><span class="n">&gt;|</span><span class="w"></span>
  56 <span class="k">infixr</span><span class="w">  </span><span class="mi">2</span><span class="w">  </span><span class="n">|&lt;</span><span class="w"></span>
  57 <span class="k">infix</span><span class="w">   </span><span class="mi">1</span><span class="w">  </span><span class="n">:=</span><span class="w">                 </span><span class="cm">(* -2 from Basis Library *)</span><span class="w"></span>
  58 <span class="k">infix</span><span class="w">   </span><span class="mi">0</span><span class="w">  </span><span class="n">before</span><span class="w"> </span><span class="n">&amp;</span><span class="w"></span>
  59
  60 <span class="cm">(* Some basic combinators *)</span><span class="w"></span>
  61 <span class="k">fun</span><span class="w"> </span><span class="n">const</span><span class="w"> </span><span class="n">x</span><span class="w"> </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>
  62 <span class="k">fun</span><span class="w"> </span><span class="n">cross</span><span class="w"> </span><span class="p">(</span><span class="n">f</span><span class="p">,</span><span class="w"> </span><span class="n">g</span><span class="p">)</span><span class="w"> </span><span class="p">(</span><span class="n">x</span><span class="p">,</span><span class="w"> </span><span class="n">y</span><span class="p">)</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="p">(</span><span class="n">f</span><span class="w"> </span><span class="n">x</span><span class="p">,</span><span class="w"> </span><span class="n">g</span><span class="w"> </span><span class="n">y</span><span class="p">)</span><span class="w"></span>
  63 <span class="k">fun</span><span class="w"> </span><span class="n">curry</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="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="p">(</span><span class="n">x</span><span class="p">,</span><span class="w"> </span><span class="n">y</span><span class="p">)</span><span class="w"></span>
  64 <span class="k">fun</span><span class="w"> </span><span class="n">fail</span><span class="w"> </span><span class="n">e</span><span class="w"> </span><span class="p">_</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="k">raise</span><span class="w"> </span><span class="n">e</span><span class="w"></span>
  65 <span class="k">fun</span><span class="w"> </span><span class="n">id</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">x</span><span class="w"></span>
  66
  67 <span class="cm">(* Product type *)</span><span class="w"></span>
  68 <span class="k">datatype</span><span class="w"> </span><span class="p">(</span><span class="n">&#39;a</span><span class="p">,</span><span class="w"> </span><span class="n">&#39;b</span><span class="p">)</span><span class="w"> </span><span class="n">product</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">&amp;</span><span class="w"> </span><span class="k">of</span><span class="w"> </span><span class="n">&#39;a</span><span class="w"> </span><span class="n">*</span><span class="w"> </span><span class="n">&#39;b</span><span class="w"></span>
  69
  70 <span class="cm">(* Sum type *)</span><span class="w"></span>
  71 <span class="k">datatype</span><span class="w"> </span><span class="p">(</span><span class="n">&#39;a</span><span class="p">,</span><span class="w"> </span><span class="n">&#39;b</span><span class="p">)</span><span class="w"> </span><span class="n">sum</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">INL</span><span class="w"> </span><span class="k">of</span><span class="w"> </span><span class="n">&#39;a</span><span class="w"> </span><span class="p">|</span><span class="w"> </span><span class="n">INR</span><span class="w"> </span><span class="k">of</span><span class="w"> </span><span class="n">&#39;b</span><span class="w"></span>
  72
  73 <span class="cm">(* Some type shorthands *)</span><span class="w"></span>
  74 <span class="k">type</span><span class="w"> </span><span class="n">&#39;a</span><span class="w"> </span><span class="n">uop</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">&#39;a</span><span class="w"> </span><span class="p">-&gt;</span><span class="w"> </span><span class="n">&#39;a</span><span class="w"></span>
  75 <span class="k">type</span><span class="w"> </span><span class="n">&#39;a</span><span class="w"> </span><span class="n">fix</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">&#39;a</span><span class="w"> </span><span class="n">uop</span><span class="w"> </span><span class="p">-&gt;</span><span class="w"> </span><span class="n">&#39;a</span><span class="w"></span>
  76 <span class="k">type</span><span class="w"> </span><span class="n">&#39;a</span><span class="w"> </span><span class="n">thunk</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">unit</span><span class="w"> </span><span class="p">-&gt;</span><span class="w"> </span><span class="n">&#39;a</span><span class="w"></span>
  77 <span class="k">type</span><span class="w"> </span><span class="n">&#39;a</span><span class="w"> </span><span class="n">effect</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="n">&#39;a</span><span class="w"> </span><span class="p">-&gt;</span><span class="w"> </span><span class="n">unit</span><span class="w"></span>
  78 <span class="k">type</span><span class="w"> </span><span class="p">(</span><span class="n">&#39;a</span><span class="p">,</span><span class="w"> </span><span class="n">&#39;b</span><span class="p">)</span><span class="w"> </span><span class="n">emb</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="p">(</span><span class="n">&#39;a</span><span class="w"> </span><span class="p">-&gt;</span><span class="w"> </span><span class="n">&#39;b</span><span class="p">)</span><span class="w"> </span><span class="n">*</span><span class="w"> </span><span class="p">(</span><span class="n">&#39;b</span><span class="w"> </span><span class="p">-&gt;</span><span class="w"> </span><span class="n">&#39;a</span><span class="p">)</span><span class="w"></span>
  79
  80 <span class="cm">(* Infixing, sectioning, and application operators *)</span><span class="w"></span>
  81 <span class="k">fun</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="n">&lt;\</span><span class="w"> </span><span class="n">f</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="k">fn</span><span class="w"> </span><span class="n">y</span><span class="w"> </span><span class="p">=&gt;</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="p">,</span><span class="w"> </span><span class="n">y</span><span class="p">)</span><span class="w"></span>
  82 <span class="k">fun</span><span class="w"> </span><span class="n">f</span><span class="w"> </span><span class="n">\&gt;</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>
  83 <span class="k">fun</span><span class="w"> </span><span class="n">f</span><span class="w"> </span><span class="n">/&gt;</span><span class="w"> </span><span class="n">y</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="k">fn</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="p">=&gt;</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="p">,</span><span class="w"> </span><span class="n">y</span><span class="p">)</span><span class="w"></span>
  84 <span class="k">fun</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="n">&lt;/</span><span class="w"> </span><span class="n">f</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">x</span><span class="w"></span>
  85
  86 <span class="cm">(* Piping operators *)</span><span class="w"></span>
  87 <span class="k">val</span><span class="w"> </span><span class="k">op</span><span class="n">&gt;|</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="k">op</span><span class="n">&lt;/</span><span class="w"></span>
  88 <span class="k">val</span><span class="w"> </span><span class="k">op</span><span class="n">|&lt;</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="k">op</span><span class="n">\&gt;</span><span class="w"></span>
  89 </pre></div></div></div>
  90 </div>
  91 </div>
  92 </div>
  93 <div id="footnotes"><hr></div>
  94 <div id="footer">
  95 <div id="footer-text">
  96 </div>
  97 <div id="footer-badges">
  98 </div>
  99 </div>
 100 </body>
 101 </html>