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| 58 | <span id="if-Statement"></span><div class="header">
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| 59 | <p>
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| 60 | Next: <a href="if_002delse-Statement.html" accesskey="n" rel="next">if-else Statement</a>, Previous: <a href="Expression-Statement.html" accesskey="p" rel="prev">Expression Statement</a>, Up: <a href="Statements.html" accesskey="u" rel="up">Statements</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Symbol-Index.html" title="Index" rel="index">Index</a>]</p>
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| 61 | </div>
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| 62 | <hr>
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| 63 | <span id="if-Statement-1"></span><h3 class="section">19.2 <code>if</code> Statement</h3>
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| 64 | <span id="index-if-statement"></span>
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| 65 | <span id="index-statement_002c-if"></span>
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| 66 | <span id="index-if"></span>
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| 67 |
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| 68 | <p>An <code>if</code> statement computes an expression to decide
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| 69 | whether to execute the following statement or not.
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| 70 | It looks like this:
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| 71 | </p>
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| 72 | <div class="example">
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| 73 | <pre class="example">if (<var>condition</var>)
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| 74 | <var>execute-if-true</var>
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| 75 | </pre></div>
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| 76 |
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| 77 | <p>The first thing this does is compute the value of <var>condition</var>. If
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| 78 | that is true (nonzero), then it executes the statement
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| 79 | <var>execute-if-true</var>. If the value of <var>condition</var> is false
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| 80 | (zero), it doesn’t execute <var>execute-if-true</var>; instead, it does
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| 81 | nothing.
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| 82 | </p>
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| 83 | <p>This is a <em>complex statement</em> because it contains a component
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| 84 | <var>if-true-substatement</var> that is a nested statement. It must be one
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| 85 | and only one statement. The way to put multiple statements there is
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| 86 | to group them into a <em>block</em> (see <a href="Blocks.html">Blocks</a>).
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| 87 | </p>
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| 89 |
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| 90 |
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