shared_ptr::operator boolean-type
Tests if an owned resource exists.
Syntax
operator boolean-type() const;
Remarks
The operator returns a value of a type that is convertible to bool. The result of the conversion to bool is true when get() != 0, otherwise false.
Example
// std_tr1__memory__shared_ptr_operator_bool.cpp
// compile with: /EHsc
#include <memory>
#include <iostream>
int main()
{
std::shared_ptr<int> sp0;
std::shared_ptr<int> sp1(new int(5));
std::cout << "(bool)sp0 == " << std::boolalpha
<< (bool)sp0 << std::endl;
std::cout << "(bool)sp1 == " << std::boolalpha
<< (bool)sp1 << std::endl;
return (0);
}
(bool)sp0 == false (bool)sp1 == true
Requirements
Header: <memory>
Namespace: std