class template
<type_traits>

std::is_literal_type

template <class T> struct is_literal_type;
Is literal type

Trait class that identifies whether T is a literal type.

A literal type is a type that can qualify as constexpr. This is true for scalar types, references, certain classes, and arrays of any such types.

A class that is a literal type is a class (defined with class, struct or union) that:
  • has a trivial destructor,
  • every constructor call and any non-static data member that has brace- or equal- initializers is a constant expression,
  • is an aggregate type, or has at least one constexpr constructor or constructor template that is not a copy or move constructor, and
  • has all non-static data members and base classes of literal types

is_literal_type inherits from integral_constant as being either true_type or false_type, depending on whether T is a trivial type.

Template parameters

T
A complete type, or void (possible cv-qualified), or an array of unknown bound.

Member types

Inherited from integral_constant:
member typedefinition
value_typebool
typeeither true_type or false_type

Member constants

Inherited from integral_constant:
member constantdefinition
valueeither true or false

Member functions

Inherited from integral_constant:
operator bool
Returns value (public member function )

Example

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// is_literal_type example
#include <iostream>
#include <type_traits>

struct A { };
struct B { ~B(){} };

int main() {
  std::cout << std::boolalpha;
  std::cout << "is_literal_type:" << std::endl;
  std::cout << "int: " << std::is_literal_type<int>::value << std::endl;
  std::cout << "int&: " << std::is_literal_type<int&>::value << std::endl;
  std::cout << "int*: " << std::is_literal_type<int*>::value << std::endl;
  std::cout << "A: " << std::is_literal_type<A>::value << std::endl;
  std::cout << "B: " << std::is_literal_type<B>::value << std::endl;
  return 0;
}


Output:
is_literal_type:
int: true
int&: true
int*: true
A: true
B: false

See also

is_const
Is const-qualified (class template )
is_trivial
Is trivial type (class template )

C++

<type_traits>