...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
For a sequence seq and unary function object f, any returns true if f returns true for at least one element of seq.
template< typename Sequence, typename F > typename result_of::any<Sequence,F>::type any( Sequence const& seq, F f);
Table 1.39. Parameters
Parameter |
Requirement |
Description |
---|---|---|
seq |
A model of Forward Sequence, f(e) must be a valid expression, convertible to bool, for each element e in seq |
The sequence to search |
f |
A unary function object |
The search predicate |
any(seq, f);
Return type: bool
Semantics: Returns true if and only if f(e) evaluates to true for some element e in seq.
Linear. At most result_of::size<Sequence>::value comparisons.
#include <boost/fusion/algorithm/query/any.hpp> #include <boost/fusion/include/any.hpp>
struct odd { template<typename T> bool operator()(T t) const { return t % 2; } }; ... assert(any(make_vector(1,2), odd())); assert(!any(make_vector(2,4), odd()));