bool_

Synopsis

template<
      bool C
    >
struct bool_
{
    // unspecified
    // ...
};

typedef bool_<true>  true_;
typedef bool_<false> false_;

Description

A boolean Integral Constant wrapper.

Header

#include <boost/mpl/bool.hpp>

Model of

Integral Constant

Parameters

Parameter	Requirement	Description
`C`	A boolean integral constant	A value to wrap.

Expression semantics

The semantics of an expression are defined only where they differ from, or are not defined in Integral Constant.

For arbitrary integral constant c:

Expression	Semantics
`bool_<c>`	An Integral Constant `x` such that `x::value == c` and `x::value_type` is identical to `bool`.

Example

BOOST_MPL_ASSERT(( is_same< bool_<true>::value_type, bool > ));
BOOST_MPL_ASSERT(( is_same< bool_<true>, true_ > )); }
BOOST_MPL_ASSERT(( is_same< bool_<true>::type, bool_<true> > ));
BOOST_MPL_ASSERT_RELATION( bool_<true>::value, ==, true );
assert( bool_<true>() == true );