89 lines
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89 lines
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<a name="M2-Constants"></a>
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Next: <a rel="next" accesskey="n" href="M2-Types.html#M2-Types">M2 Types</a>,
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Previous: <a rel="previous" accesskey="p" href="Built_002dIn-Func_002fProc.html#Built_002dIn-Func_002fProc">Built-In Func/Proc</a>,
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Up: <a rel="up" accesskey="u" href="Modula_002d2.html#Modula_002d2">Modula-2</a>
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<h5 class="subsubsection">15.4.9.3 Constants</h5>
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<p><span class="sc">gdb</span> allows you to express the constants of Modula-2 in the following
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ways:
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<ul>
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<li>Integer constants are simply a sequence of digits. When used in an
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expression, a constant is interpreted to be type-compatible with the
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rest of the expression. Hexadecimal integers are specified by a
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trailing ‘<samp><span class="samp">H</span></samp>’, and octal integers by a trailing ‘<samp><span class="samp">B</span></samp>’.
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<li>Floating point constants appear as a sequence of digits, followed by a
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decimal point and another sequence of digits. An optional exponent can
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then be specified, in the form ‘<samp><span class="samp">E[+|-]</span><var>nnn</var></samp>’, where
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‘<samp><span class="samp">[+|-]</span><var>nnn</var></samp>’ is the desired exponent. All of the
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digits of the floating point constant must be valid decimal (base 10)
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digits.
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<li>Character constants consist of a single character enclosed by a pair of
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like quotes, either single (<code>'</code>) or double (<code>"</code>). They may
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also be expressed by their ordinal value (their <span class="sc">ascii</span> value, usually)
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followed by a ‘<samp><span class="samp">C</span></samp>’.
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<li>String constants consist of a sequence of characters enclosed by a
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pair of like quotes, either single (<code>'</code>) or double (<code>"</code>).
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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
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sequences.
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<li>Enumerated constants consist of an enumerated identifier.
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<li>Boolean constants consist of the identifiers <code>TRUE</code> and
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<code>FALSE</code>.
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<li>Pointer constants consist of integral values only.
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<li>Set constants are not yet supported.
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</ul>
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