none

Description

A metafunction returning the result type of none.

Synopsis

template<
    typename Sequence,
    typename F
    >
struct none
{
    typedef bool type;
};

Table 1.47. Parameters

Parameter	Requirement	Description
`Sequence`	A model of Forward Sequence	Operation's argument
`F`	A model of unary Polymorphic Function Object	Operation's argument

Expression Semantics

result_of::none<Sequence, F>::type

Return type: bool.

Semantics: Returns the return type of none given a sequence of type Sequence and a unary Polymorphic Function Object of type F. The return type is always bool.

Complexity

Constant.

Header

#include <boost/fusion/algorithm/query/none.hpp>