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MLton
20241230
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<h1>Identifier</h1>
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<p>In <a href="StandardML">Standard ML</a>, there are syntactically two kinds of
identifiers.</p>
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<p>Alphanumeric: starts with a letter or prime (<code>'</code>) and is followed by letters, digits, primes and underbars (<code>_</code>).</p>
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<p>Examples: <code>abc</code>, <code>ABC123</code>, <code>Abc_123</code>, <code>'a</code>.</p>
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<p>Symbolic: a sequence of the following</p>
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<pre> ! % &amp; $ # + - / : &lt; = &gt; ? @ | ~ ` ^ | *</pre>
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<p>Examples: <code>+=</code>, <code>&lt;=</code>, <code>&gt;&gt;</code>, <code>$</code>.</p>
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<p>With the exception of <code>=</code>, reserved words can not be identifiers.</p>
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<p>There are a number of different classes of identifiers, some of which
have additional syntactic rules.</p>
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<p>Identifiers not starting with a prime.</p>
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<p>value identifier (includes variables and constructors)</p>
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<p>type constructor</p>
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<p>structure identifier</p>
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<p>signature identifier</p>
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<p>functor identifier</p>
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<p>Identifiers starting with a prime.</p>
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<p>type variable</p>
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<p>Identifiers not starting with a prime and numeric labels (<code>1</code>, <code>2</code>, &#8230;&#8203;).</p>
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<p>record label</p>
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Last updated Thu Oct 21 15:53:06 2021 -0400 by Matthew Fluet.
<a href="https://github.com/MLton/mlton/commits/master/doc/guide/src/Identifier.adoc">Log</a>
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