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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
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<TITLE>Treating Variables as Booleans</TITLE>
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<div align="center"><img id="headerGraphic" src="images/sludge300.png" alt="SLUDGE"/></div>
<h2>Treating Variables as Booleans</h2>
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You can treat all variables as boolean values... that is, you can say:
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<pre>if (myVariable)</pre>
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...no matter what data type is actually in the variable. Here's how they're all treated.
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<B>Undefined:</B>
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Always equates to FALSE..
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<B>Numbers:</B>
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Equates to FALSE if it contains the value 0; TRUE for everything else.
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<B>Strings:</B>
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Always equates to TRUE.
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<B>File handles:</B>
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Always equates to TRUE.
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<B>Object types:</B>
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Always equates to TRUE.
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<B>Stacks:</B>
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Equates to FALSE if the stack is empty; TRUE for everything else.
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<B>Function handles:</B>
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Always equates to TRUE.
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<B>Animations:</B>
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Always equates to TRUE.
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<B>Costumes:</B>
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Always equates to TRUE.
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<H3>See also:</H3>
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<a href="Variable_Operations.html">Variable Operations</a>
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<P class="copyright-notice">SLUDGE and this SLUDGE documentation are <A HREF="Copyright.html">copyright</A> Hungry Software and contributors 2000-2012
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