<type_traits>

class template
<type_traits>

std::is_nothrow_constructible

template <class T, class... Args> struct is_nothrow_constructible;
Is constructible throwing no exceptions

Trait class that identifies whether T is a constructible type using the set of argument types specified by Arg, and such construction is known not to throw any exception.

This class inherits from integral_constant as being either true_type or false_type.

Template parameters

T
A complete type, or void (possible cv-qualified), or an array of unknown bound.
Args
A list of complete types (or void, possibly cv-qualified, or an array of unknown bound) representing the argument types for the constructor form, in the same order as in the constructor.
If omitted, it checks whether the type is nothrow default-constructible.

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:

Example

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

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

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

Output:
is_nothrow_constructible:
int(): true
A(): true
B(): false
B(A): true


See also