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| <h4 class="subsection">6.1.12 Implicitly convert <code>LOGICAL</code> and <code>INTEGER</code> values</h4> |
| |
| <p><a name="index-conversion_002c-to-integer-338"></a><a name="index-conversion_002c-to-logical-339"></a> |
| As an extension for backwards compatibility with other compilers, GNU |
| Fortran allows the implicit conversion of <code>LOGICAL</code> values to |
| <code>INTEGER</code> values and vice versa. When converting from a |
| <code>LOGICAL</code> to an <code>INTEGER</code>, <code>.FALSE.</code> is interpreted as |
| zero, and <code>.TRUE.</code> is interpreted as one. When converting from |
| <code>INTEGER</code> to <code>LOGICAL</code>, the value zero is interpreted as |
| <code>.FALSE.</code> and any nonzero value is interpreted as <code>.TRUE.</code>. |
| |
| <pre class="smallexample"> LOGICAL :: l |
| l = 1 |
| </pre> |
| <pre class="smallexample"> INTEGER :: i |
| i = .TRUE. |
| </pre> |
| <p>However, there is no implicit conversion of <code>INTEGER</code> values in |
| <code>if</code>-statements, nor of <code>LOGICAL</code> or <code>INTEGER</code> values |
| in I/O operations. |
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