std::shared_ptr<T>::operator bool
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std::shared_ptr
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shared_ptr::operator bool
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explicit operator bool() const noexcept;
Checks if *this stores a non-null pointer, i.e. whether get() != nullptr.
Contents
[edit] Parameters
(none)
[edit] Return value
true if *this stores a pointer, false otherwise.
[edit] 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.
[edit] 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