20
General utilities library
[utilities]
20.14
Function objects
[function.objects]
20.14.12
Polymorphic function wrappers
[func.wrap]
20.14.12.2
Class template
function
[func.wrap.func]
20.14.12.2.3
function
capacity
[func.wrap.func.cap]
explicit operator bool() const noexcept;
1
Returns:
true
if
*this
has a target, otherwise
false
.