41 lines
706 B
ReStructuredText
41 lines
706 B
ReStructuredText
.. Data Types/Miscellaneous//void_ |100
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void\_
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======
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Synopsis
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--------
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.. parsed-literal::
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struct void\_
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{
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typedef void\_ type;
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};
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template< typename T > struct is_void;
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Description
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-----------
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``void_`` is a generic type placeholder representing "nothing".
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.. In many cases, returning ``void_`` from a metafunction to signal
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an absence of the requested data leads to a simpler user code than
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having a separate metafunction specifically for the purpose of
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performing the corresponding check.
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Header
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------
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.. parsed-literal::
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#include <boost/mpl/void.hpp>
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See also
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--------
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|Data Types|, |pair|, |empty_base|, |bool_|, |int_|, |integral_c|
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