std::shared_ptr<T>::operator bool
Min standard notice:
Checks if *this stores a non-null pointer, i.e. whether get() != nullptr.
# Declarations
explicit operator bool() const noexcept;
# Return value
true if *this stores a pointer, false otherwise.
# Notes
An empty shared_ptr (where use_count() == 0) may store a non-null pointer accessible by get(), e.g. if it were created using the aliasing constructor.
# Example
#include <iostream>
#include <memory>
void report(std::shared_ptr<int> ptr)
{
if (ptr)
std::cout << "*ptr=" << *ptr << "\n";
else
std::cout << "ptr is not a valid pointer.\n";
}
int main()
{
std::shared_ptr<int> ptr;
report(ptr);
ptr = std::make_shared<int>(7);
report(ptr);
}