std::is_literal_type
From cppreference.com
Defined in header <type_traits>
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template< class T > struct is_literal_type; |
(since C++11) | |
If T is a literal type, provides the member constant value equal true. For any other type, value is false.
A literal type is any scalar type, any reference type or a class type that:
1. has a trivial destructor
2. all of its constructor calls and initializers for nonstatic data members are constant expressions
3. is an aggregate type or has at least one constexpr constructor that is not a copy or move constructor
4. all of its nonstatic data members and base classes are literal types
An array of literal types is also a literal type.
Contents |
Inherited from std::integral_constant
Member constants
value [static] |
true if T is a literal type, false otherwise (public static member constant) |
Member functions
operator bool |
converts the object to bool, returns value (public member function) |
Member types
Type | Definition |
value_type | bool |
type | std::integral_constant<bool, value> |
[edit] Notes
Only literal types may be used as parameters to or returned from constexpr functions. Only literal classes may have constexpr member functions.
[edit] Example
#include <iostream> #include <type_traits> struct A { int m; }; struct B { virtual ~B(); }; int main() { std::cout << std::boolalpha; std::cout << std::is_literal_type<A>::value << '\n'; std::cout << std::is_literal_type<B>::value << '\n'; }
Output:
true false