How to reset values in for loop in swift 2 - for-loop

Question

I'm having trouble with the following line of code:
var participants = [String]()
var dict = [String: String]()
func createDictionary() {
var hat = participants
var loopCount = 0
for (keyIndex, key) in hat.enumerate() {
var valueIndex: Int {
var index: Int
repeat {
index = Int(arc4random_uniform(UInt32(hat.count)))
loopCount++
print(loopCount)
if loopCount > participants.count + 1000 {
createDictionary()
}
} while index == keyIndex || dict.values.contains(hat[index])
return index
}
dict[key] = hat[valueIndex]
}
}
My goal is for "dict" to contain a dictionary created from "participants". This function will work most of the time, but will sometimes enter into an infinite loop. I was trying to make it so that if it loops more than 1000 times or so, that the function would repeat and try again.
I think the problem is that I can't reset the values for "keyIndex" and "key" because those are "let constants". But I'm not sure.
Is there a way to reset the loop so those values? Or have the entire function retry?

Answer 1

So if anyone is interested, I was able to figure it out. I'm still new to this, so I'm sure others would have been able to figure it out quicker :)
Anyway, I updated the code as follows:
var participants = [String]()
var dict = [String: String]()
func createDictionary() {
var hat = participants
var drawName = [String: String]()
var loopCount = 0
for (keyIndex, key) in hat.enumerate() {
var valueIndex: Int {
var index: Int
repeat {
loopCount++
index = Int(arc4random_uniform(UInt32(hat.count)))
} while index == keyIndex || drawName.values.contains(hat[index]) && loopCount < hat.count + 50
return index
}
drawName[key] = hat[valueIndex]
}
if loopCount > hat.count + 30 {
self.createDictionary()
} else {
dict = drawName
}
}
mathielo was right that I was most likely looking at this the wrong way. Basically I just instructed the loop to not loop too many times, then recalled the function if it had to try too many times to get a value. The above code works without freezing the program.