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| 32 | <link href="Function-Definitions.html" rel="up" title="Function Definitions">
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| 58 | <span id="Forward-Function-Declarations"></span><div class="header">
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| 59 | <p>
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| 60 | Next: <a href="Static-Functions.html" accesskey="n" rel="next">Static Functions</a>, Previous: <a href="Function-Parameter-Variables.html" accesskey="p" rel="prev">Function Parameter Variables</a>, Up: <a href="Function-Definitions.html" accesskey="u" rel="up">Function Definitions</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="Forward-Function-Declarations-1"></span><h4 class="subsection">22.1.2 Forward Function Declarations</h4>
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| 64 | <span id="index-forward-function-declarations"></span>
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| 65 | <span id="index-function-declarations_002c-forward"></span>
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| 66 |
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| 67 | <p>The order of the function definitions in the source code makes no
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| 68 | difference, except that each function needs to be defined or declared
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| 69 | before code uses it.
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| 70 | </p>
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| 71 | <p>The definition of a function also declares its name for the rest of
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| 72 | the containing scope. But what if you want to call the function
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| 73 | before its definition? To permit that, write a compatible declaration
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| 74 | of the same function, before the first call. A declaration that
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| 75 | prefigures a subsequent definition in this way is called a
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| 76 | <em>forward declaration</em>. The function declaration can be at top
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| 77 | level or within a block, and it applies until the end of the containing
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| 78 | scope.
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| 79 | </p>
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| 80 | <p>See <a href="Function-Declarations.html">Function Declarations</a>, for more information about these
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| 81 | declarations.
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| 82 | </p>
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| 83 |
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| 85 |
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