Typetraits

Basic Type traits in DuMu^x More...

Description

Files
file	propertysystem.hh
	The Dumux property system, traits with inheritance.
file	isvalid.hh
	A helper function for class member function introspection.
file	matrix.hh
	Type traits to be used with matrix types.
file	periodic.hh
	Type traits to detect periodicity support.
file	common/typetraits/problem.hh
	Type traits for problem classes.
file	state.hh
	Type traits to be used with matrix types.
file	common/typetraits/typetraits.hh
	Type traits.
file	utility.hh
	Utilities for template meta programming.
file	vector.hh
	Type traits to be used with vector types.

Classes
struct	Dumux::ProblemTraits< Problem >
	Type traits for problem classes. More...

Functions
template<typename Expression >
constexpr auto	Dumux::isValid (const Expression &t)
	A function that creates a test functor to do class member introspection at compile time. More...

Function Documentation

isValid()

template<typename Expression >

constexpr auto Dumux::isValid ( const Expression &  t )

constexpr

Returns

a functor that returns true if the expression is valid with a given type / object Usage: If you want to test if a class has the member function resize(std::size_t) create a test functor

auto hasResize = isValid([](auto&& c) -> decltype(c.resize(std::size_t(1))) {}; });

Note

hasResize can be constexpr in C++17 which allows lambdas in constexpr functions The you can use the test in compile time expressions

template<class T>
auto otherFunc(const T& t)
-> typename std::enable_if_t<!decltype(hasResize(myvector))::value, double>
{ return 4.0; }