std::shared_ptr<T>::operator bool

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allocator
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uninitialized_copy
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uninitialized_default_construct (C++17)
uninitialized_value_construct (C++17)
destroy (C++17)
uninitialized_default_construct_n (C++17)
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ranges::uninitialized_copy (C++20)
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ranges::uninitialized_fill_n (C++20)
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ranges::uninitialized_default_construct (C++20)
ranges::uninitialized_value_construct (C++20)
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(until C++17*)

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enable_shared_from_this

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is_sufficiently_aligned

(C++26)

C Library

malloc
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free
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std::shared_ptr

Member functions
shared_ptr::shared_ptr
shared_ptr::~shared_ptr
shared_ptr::operator=
Modifiers
shared_ptr::reset
shared_ptr::swap
Observers
shared_ptr::get
shared_ptr::operator*shared_ptr::operator->
shared_ptr::operator[] (C++17)
shared_ptr::use_count
shared_ptr::unique (until C++20*)
shared_ptr::operator bool
shared_ptr::owner_before
shared_ptr::owner_hash (C++26)
shared_ptr::owner_equal (C++26)
Non-member functions
swap(std::shared_ptr)
make_sharedmake_shared_for_overwrite (C++20)
allocate_sharedallocate_shared_for_overwrite (C++20)
static_pointer_castdynamic_pointer_castconst_pointer_castreinterpret_pointer_cast (C++17)
get_deleter
operator==operator!=operator<operator<=operator>operator>=operator<=> (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20)
operator<<
atomic_xxx functions(until C++26*)
Helper classes
atomic<std::shared_ptr> (C++20)
hash<std::shared_ptr>
Deduction guides(C++17)

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explicit operatorbool()constnoexcept;

Checks if*this stores a non-null pointer, i.e. whetherget()!= nullptr.

[edit]Parameters

(none)

[edit]Return value

true if*this stores a pointer,false otherwise.

[edit]Notes

An empty shared_ptr (whereuse_count()==0) may store a non-null pointer accessible byget(), 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";elsestd::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);}