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Showing content from https://cplusplus.com/reference/type_traits/is_copy_constructible/ below:

class template

<type_traits>

std::is_copy_constructible

template <class T> struct is_copy_constructible;

Is copy constructible

Trait class that identifies whether T is a copy constructible type.

A copy constructible type is a type that can be constructed from a value or reference of the same type. This includes scalar types and copy constructible classes.

A copy constructible class is a class that has a copy constructor (either its implicit constructor or a custom defined one).

The is_copy_constructible class inherits from integral_constant as being either true_type or false_type, depending on whether T is copy constructible.

Template parameters

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

Member types Inherited from integral_constant:

Member constants Inherited from integral_constant:
member constant definition value either true or false
Member functions Inherited from integral_constant:

operator bool: Returns value (public member function)

Example

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

struct A { };
struct B { B(B&&){} };
struct C { C(const C&){} };

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

Output:

is_copy_constructible:
int: true
A: true
B: false
C: true