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<a name="Constants-1"></a>
<h4 class="subsubsection">15.4.8.3 Constants</h4>

<p><small>GDB</small> allows you to express the constants of Modula-2 in the following
ways:
</p>
<ul>
<li> Integer constants are simply a sequence of digits.  When used in an
expression, a constant is interpreted to be type-compatible with the
rest of the expression.  Hexadecimal integers are specified by a
trailing &lsquo;<samp>H</samp>&rsquo;, and octal integers by a trailing &lsquo;<samp>B</samp>&rsquo;.

</li><li> Floating point constants appear as a sequence of digits, followed by a
decimal point and another sequence of digits.  An optional exponent can
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
&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
digits of the floating point constant must be valid decimal (base 10)
digits.

</li><li> Character constants consist of a single character enclosed by a pair of
like quotes, either single (<code>'</code>) or double (<code>&quot;</code>).  They may
also be expressed by their ordinal value (their <small>ASCII</small> value, usually)
followed by a &lsquo;<samp>C</samp>&rsquo;.

</li><li> String constants consist of a sequence of characters enclosed by a
pair of like quotes, either single (<code>'</code>) or double (<code>&quot;</code>).
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
sequences.

</li><li> Enumerated constants consist of an enumerated identifier.

</li><li> Boolean constants consist of the identifiers <code>TRUE</code> and
<code>FALSE</code>.

</li><li> Pointer constants consist of integral values only.

</li><li> Set constants are not yet supported.
</li></ul>


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