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| 55 | <H1><A NAME="SECTION009100000000000000000"></A><A NAME="if"></A> |
| 56 | <BR> |
| 57 | 7.1 The <tt class="keyword">if</tt> statement |
| 58 | </H1> |
| 59 | <a id='l2h-573' xml:id='l2h-573'></a> |
| 60 | <P> |
| 61 | The <tt class="keyword">if</tt> statement is used for conditional execution: |
| 62 | |
| 63 | <P> |
| 64 | <dl><dd class="grammar"> |
| 65 | <div class="productions"> |
| 66 | <table> |
| 67 | <tr> |
| 68 | <td><a id='tok-if_stmt' xml:id='tok-if_stmt'>if_stmt</a></td> |
| 69 | <td>::=</td> |
| 70 | <td>"if" <a class='grammartoken' href="Booleans.html#tok-expression">expression</a> ":" <a class='grammartoken' href="compound.html#tok-suite">suite</a></td></tr> |
| 71 | <tr> |
| 72 | <td></td> |
| 73 | <td></td> |
| 74 | <td><code>( "elif" <a class='grammartoken' href="Booleans.html#tok-expression">expression</a> ":" <a class='grammartoken' href="compound.html#tok-suite">suite</a> )*</code></td></tr> |
| 75 | <tr> |
| 76 | <td></td> |
| 77 | <td></td> |
| 78 | <td><code>["else" ":" <a class='grammartoken' href="compound.html#tok-suite">suite</a>]</code></td></tr> |
| 79 | </table> |
| 80 | </div> |
| 81 | <a class="grammar-footer" |
| 82 | href="grammar.txt" type="text/plain" |
| 83 | >Download entire grammar as text.</a> |
| 84 | </dd></dl> |
| 85 | |
| 86 | <P> |
| 87 | It selects exactly one of the suites by evaluating the expressions one |
| 88 | by one until one is found to be true (see section <A href="Booleans.html#Booleans">5.10</A> for |
| 89 | the definition of true and false); then that suite is executed (and no |
| 90 | other part of the <tt class="keyword">if</tt> statement is executed or evaluated). If |
| 91 | all expressions are false, the suite of the <tt class="keyword">else</tt> clause, if |
| 92 | present, is executed. |
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| 130 | <span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span> |
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