http://coderwiki.org/index.php?action=history&feed=atom&title=CastingCasting - Revision history2026-05-19T03:47:55ZRevision history for this page on the wikiMediaWiki 1.44.0http://coderwiki.org/index.php?title=Casting&diff=69&oldid=prevDylan: new2025-08-11T12:09:22Z<p>new</p>
<p><b>New page</b></p><div>'''Casting''' in programming is the process of converting a [[value]] (often stored in a [[variable]]) from one [[data type]] to another.<br />
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This changes what [[Method|methods]] we can call on the [[value]].<br />
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== Syntax ==<br />
The [[syntax]] to cast a [[value]] varies a lot by the [[programming language]].<br />
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C-style casting is done like this:<syntaxhighlight lang="c"><br />
(type)value<br />
</syntaxhighlight>For example, to cast an integer to a float, we would do:<syntaxhighlight lang="c" line="1"><br />
int number = 4;<br />
float fnumber = (float)4;<br />
printf("%f", fnumber); // 4.0<br />
</syntaxhighlight><br />
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== Lossy type conversion ==<br />
Sometimes, while a [[value]] could fit in the [[source]] data type, it can't properly fit into the [[target]] data type. For example, a decimal [[Floating point|float]] into an [[integer]].<br />
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In this case, the program may either return an [[error]], throw an [[exception]], or the value may be [[Rounding|rounded]] or [[Truncation|truncated]]. In the case of casting an [[integer]] into a [[floating point]] number, the value is [[Truncation|truncated]]:<syntaxhighlight lang="c" line="1"><br />
float f = 3.14;<br />
int i = (float)f;<br />
printf("%d", i); // 3<br />
</syntaxhighlight></div>Dylan