swap(std::move_only_function) - cppreference.com (original) (raw)
Overloads the std::swap algorithm for std::move_only_function. Exchanges the state of lhs with that of rhs. Effectively calls lhs.swap(rhs).
This function is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::move_only_function<FunctionType> is an associated class of the arguments.
[edit] Parameters
| lhs, rhs | - | std::move_only_function objects whose states to swap |
|---|
[edit] Return value
(none)
[edit] Example
#include #include #include void foo(const char* str, int x) { std::cout << "foo("" << str << "", " << x << ")\n"; } void bar(const char* str, int x) { std::cout << "bar("" << str << "", " << x << ")\n"; } int main() { std::move_only_function<void(const char*, int) const> f1{foo}; std::move_only_function<void(const char*, int) const> f2{bar}; f1("f1", 1); f2("f2", 2); std::cout << "std::ranges::swap(f1, f2);\n"; std::ranges::swap(f1, f2); // finds the hidden friend f1("f1", 1); f2("f2", 2); }
Output:
foo("f1", 1) bar("f2", 2) std::ranges::swap(f1, f2); bar("f1", 1) foo("f2", 2)