119 lines
4.1 KiB
HTML
119 lines
4.1 KiB
HTML
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<a href="intro.html"><h2>SQLite C Interface</h2></a>
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<h2>Overload A Function For A Virtual Table</h2>
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</div>
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<blockquote><pre>
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int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
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</pre></blockquote>
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<p>
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Virtual tables can provide alternative implementations of functions
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using the <a href="../vtab.html#xfindfunction">xFindFunction</a> method of the <a href="../c3ref/module.html">virtual table module</a>.
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But global versions of those functions
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must exist in order to be overloaded.</p>
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<p>This API makes sure a global version of a function with a particular
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name and number of parameters exists. If no such function exists
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before this API is called, a new function is created. The implementation
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of the new function always causes an exception to be thrown. So
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the new function is not good for anything by itself. Its only
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purpose is to be a placeholder function that can be overloaded
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by a <a href="../vtab.html">virtual table</a>.
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</p><p>See also lists of
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<a href="objlist.html">Objects</a>,
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<a href="constlist.html">Constants</a>, and
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<a href="funclist.html">Functions</a>.</p>
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