# `bool operator!=(const failure_type<A, void> &) const`

Returns true if this result is successful or its error does not compare equal to the error in the failure type sugar. Comparison is done using `operator!=` on `error_type` and `A`. If `A` is `void`, this call aliases `bool has_value() const noexcept` .

Requires: `operator!=` must be a valid expression between `error_type` and `A`, or `A` is `void`. If `error_type` is `void`, then so must be `A`.

Complexity: Whatever the underlying `operator!=` has. Constexpr and noexcept of underlying operations is propagated.

Guarantees: None.

Last revised: January 31, 2019 at 01:07:35 UTC