The std::is_trivially_copy_constructible template is a type that can be trivially constructed from a value or reference of the same type. This includes scalar types, trivially copy constructible classes and arrays of such types. This algorithm is about to test whether a type is trivially copied constructible or not. It returns the boolean value showing the same.
Header File:
#include <type_traits>
Template Class:
template <class T> struct is_trivially_copy_constructible;
If T is_trivially_copy_constructible, then it inherits from true_type else inherits from false_type.
Syntax:
std::is_trivially_copy_constructible<int>::value std::is_trivially_copy_constructible<class T>::value
Parameter: This template accepts a single parameter T(Trait class) to check if T is trivially copy constructible or not.
Return Value: This template return a boolean variable as shown below:
- True: If the type is trivially copy constructible.
- False: If the type is not trivially copy constructible.
Below programs illustrates the std::is_trivially_copy_constructible template in C/C++:
Program 1:
// C++ program to illustrate // is_trivially_copy_constructible #include <iostream> #include <type_traits> using namespace std;
// Struct Class struct A {
}; struct B {
B( const B&) {}
}; struct C {
virtual void fn() {}
}; // Driver Code int main()
{ cout << boolalpha;
cout << "is_trivially_copy_constructible: "
<< endl;
cout << "int: " << is_trivially_copy_constructible< int >::value
<< endl;
cout << "A: " << is_trivially_copy_constructible<A>::value
<< endl;
cout << "B: " << is_trivially_copy_constructible<B>::value
<< endl;
cout << "C: " << is_trivially_copy_constructible<C>::value
<< endl;
return 0;
} |
is_trivially_copy_constructible: int: true A: true B: false C: false
Program 2:
// C++ program to illustrate // is_trivially_copy_constructible #include <iostream> #include <type_traits> using namespace std;
// Structure struct Ex1 {
string str;
}; struct Ex2 {
int n;
Ex2( const Ex2&) = default ;
}; // Driver Code int main()
{ cout << boolalpha;
cout << "Ex1 is copy-constructible? " ;
cout << is_copy_constructible<Ex1>::value
<< endl;
cout << "Ex1 is trivially copy-constructible? " ;
cout << is_trivially_copy_constructible<Ex1>::value
<< endl;
cout << "Ex2 is trivially copy-constructible? " ;
cout << is_trivially_copy_constructible<Ex2>::value
<< endl;
cout << "Ex2 is nothrow copy-constructible? " ;
cout << is_nothrow_copy_constructible<Ex2>::value
<< endl;
} |
Ex1 is copy-constructible? true Ex1 is trivially copy-constructible? false Ex2 is trivially copy-constructible? true Ex2 is nothrow copy-constructible? true