23 General utilities library [utilities]

23.14 Function objects [function.objects]

23.14.13 Polymorphic function wrappers [func.wrap]

23.14.13.2 Class template function [func.wrap.func]

23.14.13.2.2 function modifiers [func.wrap.func.mod]

void swap(function& other) noexcept;
Effects: Interchanges the targets of *this and other.