C++

Reference

<type_traits>

class template
<type_traits>

std::is_compound

template <class T> struct is_compound;
Is compound type

Trait class that identifies whether T is a compound type.

It inherits from integral_constant as being either true_type or false_type, depending on whether T is a compound type (i.e., not a fundamental type).

This is a compound type trait defined with the same behavior as:
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template<class T>
struct is_compound : std::integral_constant <bool,!is_fundamental<T>::value> {};

Template parameters

T
A type.

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_compound example
#include <iostream>
#include <type_traits>

int main() {
  std::cout << std::boolalpha;
  std::cout << "is_compound:" << std::endl;
  std::cout << "long int: " << std::is_compound<long int>::value << std::endl;
  std::cout << "float: " << std::is_compound<float>::value << std::endl;
  std::cout << "float*: " << std::is_compound<float*>::value << std::endl;
  std::cout << "float&: " << std::is_compound<float&>::value << std::endl;
  std::cout << "decltype(nullptr): " << std::is_compound<decltype(nullptr)>::value << std::endl;
  return 0;
}

Output:
is_compound:
long int: false
float: false
float*: true
float&: true
decltype(nullptr): false


See also

is_fundamental
Is fundamental type (class template)
is_pointer
Is pointer (class template)
is_member_pointer
Is member pointer type (class template)
is_enum
Is enum (class template)
is_union
Is union (class template)
is_class
Is non-union class (class template)