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<H1><A NAME="SECTION004300000000000000000"> </A><a name="l2h-9"> </a>
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2.3 Identifiers and keywords
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<P>
Identifiers (also referred to as <i>names</i>) are described by the following
lexical definitions:
<P>
<dl><dd class="grammar">
<div class="productions">
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<td><code><a name="tok-identifier">identifier</a></code></td>
<td> ::= </td>
<td><code>(<a href="identifiers.html#tok-letter">letter</a>|"_") (<a href="identifiers.html#tok-letter">letter</a> | <a href="identifiers.html#tok-digit">digit</a> | "_")*</code></td></tr>
<tr valign="baseline">
<td><code><a name="tok-letter">letter</a></code></td>
<td> ::= </td>
<td><code><a href="identifiers.html#tok-lowercase">lowercase</a> | <a href="identifiers.html#tok-uppercase">uppercase</a></code></td></tr>
<tr valign="baseline">
<td><code><a name="tok-lowercase">lowercase</a></code></td>
<td> ::= </td>
<td><code>"a"..."z"</code></td></tr>
<tr valign="baseline">
<td><code><a name="tok-uppercase">uppercase</a></code></td>
<td> ::= </td>
<td><code>"A"..."Z"</code></td></tr>
<tr valign="baseline">
<td><code><a name="tok-digit">digit</a></code></td>
<td> ::= </td>
<td><code>"0"..."9"</code></td></tr>
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<a class="grammar-footer"
href="grammar.txt" type="text/plain"
>Download entire grammar as text.</a>
</dd></dl>
<P>
Identifiers are unlimited in length. Case is significant.
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<LI><A href="keywords.html">2.3.1 Keywords</a>
<LI><A href="id-classes.html">2.3.2 Reserved classes of identifiers</a>
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<span class="release-info">Release 2.2, documentation updated on December 21, 2001.</span>
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