std::is_move_constructible in C++ with Examples

The std::is_move_constructible template of C++ STL is present in the <type_traits> header file. The std::is_move_constructible template of C++ STL is used to check whether the T is move constructible (that can be constructed from an rvalue reference of its type) or not. It returns the boolean value either true or false.

Header File:

#include<type_traits>

Template Class:

template< class T >
struct is_move_convertible;

Syntax:

std::is_move_constructible< datatype >::value << '\n'

Parameters: The template std::is_move_constructible accepts a single parameter T (Trait class) to check whether T is move constructible type or not.

Return Value:

• True: If a given data type T is is_move_constructible.
• False: If a given data type T is not is_move_constructible.

Below is the program to demonstrate std::is_move_constructible:

Program:

// C++ program to illustrate
// std::is_move_constructible
#include <bits/stdc++.h>
#include <type_traits>

using namespace std;

// Declare structures
struct B {
};
struct A {
    A& operator=(A&) = delete;
};

class C {
    int n;
    C(C&&) = default;
};

class D {
    D(const D&) {}
};

// Driver Code
int main()
{
    cout << boolalpha;

    // Check if char is move constructible or not
    cout << "char: "
         << is_move_constructible<char>::value
         << endl;

    // Check if struct A is move constructible or not
    cout << "struct A: "
         << is_move_constructible<A>::value
         << endl;

    // Check if struct B is move constructible or not
    cout << "struct B: "
         << is_move_constructible<B>::value
         << endl;

    // Check if class C is move constructible or not
    cout << "class C: "
         << is_move_constructible<C>::value
         << endl;

    // Check if class D is move constructible or not
    cout << "class D: "
         << is_move_constructible<D>::value
         << endl;
    return 0;
}

Output:

char: true
struct A: true
struct B: true
class C: false
class D: false

Reference: http://www.cplusplus.com/reference/type_traits/is_move_constructible/