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  1. <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
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  3. <!-- This file documents the GNU Assembler "as".
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  15. <title>Symbol Intro (Using as)</title>
  16. <meta name="description" content="Symbol Intro (Using as)">
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  21. <link href="index.html#Top" rel="start" title="Top">
  22. <link href="AS-Index.html#AS-Index" rel="index" title="AS Index">
  23. <link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
  24. <link href="Syntax.html#Syntax" rel="up" title="Syntax">
  25. <link href="Statements.html#Statements" rel="next" title="Statements">
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  56. <a name="Symbol-Intro"></a>
  57. <div class="header">
  58. <p>
  59. Next: <a href="Statements.html#Statements" accesskey="n" rel="next">Statements</a>, Previous: <a href="Comments.html#Comments" accesskey="p" rel="prev">Comments</a>, Up: <a href="Syntax.html#Syntax" accesskey="u" rel="up">Syntax</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
  60. </div>
  61. <hr>
  62. <a name="Symbols-1"></a>
  63. <h3 class="section">3.4 Symbols</h3>
  64. <a name="index-characters-used-in-symbols"></a>
  65. <p>A <em>symbol</em> is one or more characters chosen from the set of all
  66. letters (both upper and lower case), digits and the three characters
  67. &lsquo;<samp>_.$</samp>&rsquo;.
  68. On most machines, you can also use <code>$</code> in symbol names; exceptions
  69. are noted in <a href="Machine-Dependencies.html#Machine-Dependencies">Machine Dependencies</a>.
  70. No symbol may begin with a digit. Case is significant.
  71. There is no length limit; all characters are significant. Multibyte characters
  72. are supported. Symbols are delimited by characters not in that set, or by the
  73. beginning of a file (since the source program must end with a newline, the end
  74. of a file is not a possible symbol delimiter). See <a href="Symbols.html#Symbols">Symbols</a>.
  75. </p>
  76. <p>Symbol names may also be enclosed in double quote <code>&quot;</code> characters. In such
  77. cases any characters are allowed, except for the NUL character. If a double
  78. quote character is to be included in the symbol name it must be preceeded by a
  79. backslash <code>\</code> character.
  80. <a name="index-length-of-symbols"></a>
  81. </p>
  82. </body>
  83. </html>