func test1(user: String, completion: @escaping (TestModel) -> Void) {
test2(user: "test", completion: completion as! (Any) -> Void //failed here)
}
func test2(user: String, completion: @escaping (Any) -> Void) {
completion(user)
}
I want to pass test1's closure to test2, but test2's closure may have multiple type, it get error when run, EXC_BAD_INSTRUCTION
Is it passable to do this?
This is a misuse of a generic. If you don't care what type is used as the argument to completion, type its parameter as Any:
func test(user: String, completion: @escaping (Any) -> Void) {
completion(user)
}
completion in the above method must take an argument of type T. So anything that you use as an argument to completion must also be of type T. So user must be of type T, i.e.
func test<T>(user: T, completion: @escaping (T) -> Void)
{
completion(user)
}
user type should match the completion function's parameter type, then this is right (and my answer is not).