enables fast switching between certain letters in Strings

Abstract - StringReplacer.md

String Replacer

enables fast switching between certain letters in Strings

var s = StringReplacer(("E", "3"), ("g", "9"), ("O", "0"), ("o", "0"), ("l", "1"))

s["1"] = "l"

var str = "hallo"

s.replace(in: &str)
print(str) // Prints "ha110"
s.replace(in: &str)
print(str) // Prints "hall0"

StringReplacer.swift

struct StringReplacer {
    typealias Element = (key: Character, value: Character)
    
    var replacements = [Character : Character]()
    
    init() {}
    init(_ values: Element...) {
        for v in values {
            replacements[v.key] = v.value
        }
    }
    
    subscript(str: Character) -> Character? {
        get { return replacements[str] }
        set { replacements[str] = newValue }
    }
    
    func replace(in str: inout String) {
        for i in str.characters.indices {
            let c = str.characters[i]
            if let r = self.replacements[c] {
                str.replaceSubrange(i...i, with: "\(r)")
            }
        }
    }
}