Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::proto::is_transform — Boolean metafunction which tells whether a type is a PrimitiveTransform or not.
// In header: <boost/proto/traits.hpp>
template<typename T>
struct is_transform : mpl::bool_<true-or-false> {
};
proto::is_transform<> is used by the
proto::make<>
transform to determine whether a type R represents a
PrimitiveTransform to apply, or whether it merely represents itself.
It is also used by the
proto::call<>
transform to determine whether the function types R(),
R(A1), and R(A1, A2) should
be passed the expression, state and data parameters (as needed).
Unless specialized for a type
T, proto::is_transform<T>::value
is computed as follows:
If T is a class type that inherits directly or indirectly from
an instantiation of
proto::transform<>,
proto::is_transform<T>::value is true.
Otherwise, proto::is_transform<T>::value
is false.