std::shared_ptr::operator bool
From cppreference.com
< cpp | memory | shared ptr
explicit operator bool() const noexcept; |
||
Checks if *this stores a non-null pointer, i.e. whether get() != nullptr.
Parameters
(none)
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
Run this code
#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); }
Output:
ptr is not a valid pointer. *ptr=7
See also
returns the stored pointer (public member function) |