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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 ‘<samp><span class="samp">H</span></samp>’, and octal integers by a trailing ‘<samp><span class="samp">B</span></samp>’. |
| |
| <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 ‘<samp><span class="samp">E[+|-]</span><var>nnn</var></samp>’, where |
| ‘<samp><span class="samp">[+|-]</span><var>nnn</var></samp>’ 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 ‘<samp><span class="samp">C</span></samp>’. |
| |
| <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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