Best way to implement pointer in Swift [closed] - objective-c

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In Objective-C it is quite common to use boolean pointers to stop an enumeration e.g.:
[myArray rh_iterate:^(id element, int index, BOOL *stop){
// Do cool stuff
*stop = YES;
}];
I've implemented this like:
// This is in a category of NSArray
- (void)rh_iterate:(void (^)(id, int, BOOL *))block
{
if (!block) { return; }
BOOL stop = NO;
for (int i = 0; i < self.count; i++) {
block(self[i], i, &stop);
if (stop) { return; }
}
}
I'm now implementing my version of this in Swift but am not relying on any Objective-C source code. I know that swift likes to restrict the access of pointers so what's the best way to go about implementing this? (Ideally completely avoiding pointers.)
EDIT:
The most direct way is:
func rh_iterate(callback: (Element, Int, UnsafeMutablePointer<Bool>) -> ()) {
var stop: Bool = false
for (index, element) in self.enumerate() {
callback(element, index, &stop)
if stop { return }
}
}

Answer 1

Since AMomchilov deleted his answer, I'll put it back.
The direct equivalent to the BOOL* pattern would be an inout variable
extension Array
{
func iterateWithStop(closure: (Element, inout shouldStop: Bool) -> ()) -> Bool
{
var shouldStop = false
for e in self
{
guard !shouldStop else { return false }
closure(e, shouldStop: &shouldStop)
}
return !shouldStop
}
}
The function returns true if the iteration completed without the closure trying to stop it, false if the closure did try to stop it.
You would use it like this:
let myArray = [1, 2, 3, -1, 4]
var sum = 0
let didProcessAllElements = myArray.iterateWithStop{ e, shouldStop in
if e < 0
{
shouldStop = true
}
else
{
sum += e
}
}
// sum == 6
(tested in a playground on Swift 2.2)