std::function::operator()
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| R operator()( ArgTypes... args ) const; |
(начиная с C++11) | |
Calls the stored callable function target with the parameters args.
Содержание |
[править] Параметры
| args | - | parameters to pass to the stored callable function target |
[править] Возвращаемое значение
None if R is void. Otherwise the return value of the invocation of the stored callable object.
[править] Исключения
- std::bad_function_call if *this does not store a callable function target, !*this == true.
[править] Пример
The following example shows how std::function can passed to other functions by value. Also, it shown how std::function can store lambdas.
#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); }
Вывод:
1 2 42
[править] См. также
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