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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 | ||
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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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