Generate a random character from a range of characters (Unicode safe)

RandomCharacter.swift

func randomCharacter<T: IntervalType where T.Bound == Character>(inRange range: T) -> Character {
    let startScalars = String(range.start).unicodeScalars
    let startCode = startScalars[startScalars.startIndex].value
    
    let endScalars = String(range.end).unicodeScalars
    let endCode = endScalars[endScalars.startIndex].value
    
    let characterCount = distance(startCode, endCode) + 1
    let rndOffset = Int(arc4random_uniform(UInt32(characterCount)))
    
    return Character(UnicodeScalar(startCode + rndOffset))
}

Example:

for i in 0..<10 {
    print(randomCharacter(inRange: "A"..."Z"))
}

LINCBKRGEN

This code was not working when I was trying to use it.

I kept getting an error: "Ambiguous use of operator '+'" on line 11.

The reason for this is rndOffset is being returned as an Int, but startCode is UInt32.

To fix this add Int() to startCode in line 11 so both startCode and rndOffset are of the same type.

func randomCharacter<T: IntervalType where T.Bound == Character>(inRange range: T) -> Character {
    let startScalars = String(range.start).unicodeScalars
    let startCode = startScalars[startScalars.startIndex].value

    let endScalars = String(range.end).unicodeScalars
    let endCode = endScalars[endScalars.startIndex].value

    let characterCount = distance(startCode, endCode) + 1
    let rndOffset = Int(arc4random_uniform(UInt32(characterCount)))

    return Character(UnicodeScalar(Int(startCode) + rndOffset))
}