std::function::operator()
From cppreference.com
                    
                                        
                    < cpp | utility | functional | function
                    
                                                            
                    | R operator()( ArgTypes... args ) const; | (since C++11) | |
Calls the stored callable function target with the parameters args.
| Contents | 
[edit] Parameters
| args | - | parameters to pass to the stored callable function target | 
[edit] Return value
None if R is void. Otherwise the return value of the invocation of the stored callable object.
[edit] Exceptions
- std::bad_function_call if *this does not store a callable function target, !*this == true.
[edit] Example
The following example shows how std::function can passed to other functions by value. Also, it shown how std::function can store lambdas.
Run this code
#include <iostream> #include <functional> void call(std::function<int()> f) // can be passed by value { std::cout << f() << '\n'; } int normal_function() { return 42; } int main() { int n = 1; std::function<int()> f = [&n](){ return n; }; call(f); n = 2; call(f); f = normal_function; call(f); }
Output:
1 2 42
[edit] See also
| This section is incomplete | 


