20 General utilities library [utilities]

20.7 Smart pointers [smartptr]

20.7.2 Shared-ownership pointers [util.smartptr]

20.7.2.3 Class template weak_ptr [util.smartptr.weak]

20.7.2.3.4 weak_ptr modifiers [util.smartptr.weak.mod]

void swap(weak_ptr& r) noexcept;

Effects: Exchanges the contents of *this and r.

void reset() noexcept;

Effects: Equivalent to weak_ptr().swap(*this).