Michael Fabain Dirks
61 lines
2.0 KiB
HTML
61 lines
2.0 KiB
HTML
<html>
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<head>
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<meta http-equiv="Content-Type"
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content="text/html; charset=iso-8859-1">
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<title>Language Reference - Constants</title>
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<link rel="stylesheet" href="lang_ref.css" type="text/css">
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</head>
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<body><br>
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<span class="Command"> Constants </span>
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<blockquote>
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<p>Constants may be of any basic data type. Constants are variables that have
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fixed values that will not change (ever) during the course of your program.
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These are useful tools for things like screen resolution variables, etc.</p>
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<p><b>Floating point constants</b> must include a decimal point. </p>
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<p>For example: </p>
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</blockquote>
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<p align=left>
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<blockquote>
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<blockquote><i> '5' is an integer constant, but '5.0' is a floating point constant.
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</i> </blockquote>
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<p><b>String constants</b> must be surrounded by quotation marks, for example:</p>
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</blockquote>
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<p>
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<p align=left>
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<blockquote>
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<blockquote> <i>"This is a string constant". </i> </blockquote>
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<p>The '<b>Const</b>' keyword is used to assign an identifier to a constant.
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For example:</p>
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</blockquote>
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<p>
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<p align=left>
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<blockquote>
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<blockquote><i> Const one_hundred=100 </i> </blockquote>
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<p> You can then use the identifier 'one_hundred' anywhere in your program instead
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of '100'. </p>
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</blockquote>
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<p>
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<blockquote>
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<p>A more useful example might be:</p>
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</blockquote>
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<p align=left>
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<blockquote>
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<blockquote>
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<i>Const width=640,height=480 </i> </blockquote>
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<p> You can then use the more readable '<i>width</i>' and '<i>height</i>' throughout
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your program instead of '640' and '480'. </p>
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<p>Also, if you ever decide to change the width and height values, you only
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have to do so at one place in the program.<br>
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</p>
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<p> There are two built-in <b>Integer constants</b> - 'true' and 'false'. 'true'
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is equal to 1, and 'false' is equal to 0. </p>
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<p> There is also a built in <b>floating point constant</b> for Pi. </p>
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<p> </p>
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</blockquote>
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</body>
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</html> |