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<h5 class="subsubsection">15.4.9.3 Constants</h5>

<p><span class="sc">gdb</span> allows you to express the constants of Modula-2 in the following
ways:

     <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><span class="samp">H</span></samp>&rsquo;, and octal integers by a trailing &lsquo;<samp><span class="samp">B</span></samp>&rsquo;.

     <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><span class="samp">E[+|-]</span><var>nnn</var></samp>&rsquo;, where
&lsquo;<samp><span class="samp">[+|-]</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>Character constants consist of a single character enclosed by a pair of
like quotes, either single (<code>'</code>) or double (<code>"</code>).  They may
also be expressed by their ordinal value (their <span class="sc">ascii</span> value, usually)
followed by a &lsquo;<samp><span class="samp">C</span></samp>&rsquo;.

     <li>String constants consist of a sequence of characters enclosed by a
pair of like quotes, either single (<code>'</code>) or double (<code>"</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>Enumerated constants consist of an enumerated identifier.

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

     <li>Pointer constants consist of integral values only.

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

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