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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>
36 <a href="InfixingOperators">InfixingOperators</a>, and
41 <a href="ProductType">ProductType</a>
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"><></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="n"><=</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"><\</span><span class="w"> </span><span class="n">\></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"></</span><span class="w"> </span><span class="n">/></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">>|</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">|<</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">&</span><span class="w"></span>
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>
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">'a</span><span class="p">,</span><span class="w"> </span><span class="n">'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">&</span><span class="w"> </span><span class="k">of</span><span class="w"> </span><span class="n">'a</span><span class="w"> </span><span class="n">*</span><span class="w"> </span><span class="n">'b</span><span class="w"></span>
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">'a</span><span class="p">,</span><span class="w"> </span><span class="n">'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">'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">'b</span><span class="w"></span>
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">'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">'a</span><span class="w"> </span><span class="p">-></span><span class="w"> </span><span class="n">'a</span><span class="w"></span>
75 <span class="k">type</span><span class="w"> </span><span class="n">'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">'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">'a</span><span class="w"></span>
76 <span class="k">type</span><span class="w"> </span><span class="n">'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">-></span><span class="w"> </span><span class="n">'a</span><span class="w"></span>
77 <span class="k">type</span><span class="w"> </span><span class="n">'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">'a</span><span class="w"> </span><span class="p">-></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">'a</span><span class="p">,</span><span class="w"> </span><span class="n">'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">'a</span><span class="w"> </span><span class="p">-></span><span class="w"> </span><span class="n">'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">'b</span><span class="w"> </span><span class="p">-></span><span class="w"> </span><span class="n">'a</span><span class="p">)</span><span class="w"></span>
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"><\</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">=></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">\></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">/></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">=></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"></</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>
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">>|</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="k">op</span><span class="n"></</span><span class="w"></span>
88 <span class="k">val</span><span class="w"> </span><span class="k">op</span><span class="n">|<</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="k">op</span><span class="n">\></span><span class="w"></span>
89 </pre></div></div></div>
93 <div id="footnotes"><hr></div>
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