### execution::can_set_error

A type trait that determines whether a `set_error` expression is well-formed.

    template<
        typename R,
        typename E>
    struct can_set_error

Class template `can_set_error` is a trait that is derived from `true_type` if the expression `execution::set_error(std::declval<R>(), std::declval<E>())` is well formed; otherwise `false_type`.

##### Requirements

Header: `asio/execution/set_error.hpp`

Convenience header: `asio/execution.hpp`