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  63. <a name="Constants-1"></a>
  64. <h4 class="subsubsection">15.4.9.3 Constants</h4>
  65. <p><small>GDB</small> allows you to express the constants of Modula-2 in the following
  66. ways:
  67. </p>
  68. <ul>
  69. <li> Integer constants are simply a sequence of digits. When used in an
  70. expression, a constant is interpreted to be type-compatible with the
  71. rest of the expression. Hexadecimal integers are specified by a
  72. trailing &lsquo;<samp>H</samp>&rsquo;, and octal integers by a trailing &lsquo;<samp>B</samp>&rsquo;.
  73. </li><li> Floating point constants appear as a sequence of digits, followed by a
  74. decimal point and another sequence of digits. An optional exponent can
  75. then be specified, in the form &lsquo;<samp>E<span class="roman">[</span>+<span class="roman">|</span>-<span class="roman">]</span><var>nnn</var></samp>&rsquo;, where
  76. &lsquo;<samp><span class="roman">[</span>+<span class="roman">|</span>-<span class="roman">]</span><var>nnn</var></samp>&rsquo; is the desired exponent. All of the
  77. digits of the floating point constant must be valid decimal (base 10)
  78. digits.
  79. </li><li> Character constants consist of a single character enclosed by a pair of
  80. like quotes, either single (<code>'</code>) or double (<code>&quot;</code>). They may
  81. also be expressed by their ordinal value (their <small>ASCII</small> value, usually)
  82. followed by a &lsquo;<samp>C</samp>&rsquo;.
  83. </li><li> String constants consist of a sequence of characters enclosed by a
  84. pair of like quotes, either single (<code>'</code>) or double (<code>&quot;</code>).
  85. Escape sequences in the style of C are also allowed. See <a href="C-Constants.html#C-Constants">C and C<tt>++</tt> Constants</a>, for a brief explanation of escape
  86. sequences.
  87. </li><li> Enumerated constants consist of an enumerated identifier.
  88. </li><li> Boolean constants consist of the identifiers <code>TRUE</code> and
  89. <code>FALSE</code>.
  90. </li><li> Pointer constants consist of integral values only.
  91. </li><li> Set constants are not yet supported.
  92. </li></ul>
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