...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
Returns the result type of filter_if
given the sequence
and unary MPL
Lambda Expression predicate type.
template< typename Sequence, typename Pred > struct filter_if { typedef unspecified type; };
Table 1.85. Parameter
Parameter |
Requirement |
Description |
---|---|---|
|
A model of Forward Sequence |
Operation's argument |
|
A unary MPL Lambda Expression |
Type to retain |
result_of::filter_if
<Sequence, Pred>::type
Return type:
Sequence
implements the Associative
Sequence model.
Semantics: Returns a sequence containing
the elements of Sequence
for which Pred
evaluates
to boost::mpl::true_
.
Constant.
#include <boost/fusion/algorithm/transformation/filter_if.hpp> #include <boost/fusion/include/filter_if.hpp>