2014-04-26 10:52:28 -04:00
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idempotent
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2014-04-26 11:54:15 -04:00
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adj. [from mathematical techspeak] Acting as if used only once, even if used
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multiple times. This term is often used with respect to C header files,
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which contain common definitions and declarations to be included by several
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source files. If a header file is ever included twice during the same
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compilation (perhaps due to nested #include files), compilation errors can
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result unless the header file has protected itself against multiple
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inclusion; a header file so protected is said to be idempotent. The term can
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also be used to describe an initialization subroutine that is arranged to
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perform some critical action exactly once, even if the routine is called
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several times.
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