in Sources/Tokenizers/Normalizer.swift [309:320]
func replace(_ text: String) -> String {
switch self {
case let .regexp(regexp, replacement):
let range = NSRange(text.startIndex..., in: text)
let replaced = regexp.stringByReplacingMatches(
in: text, options: [], range: range, withTemplate: replacement
)
return replaced
case let .string(toReplace, replacement):
return text.replacingOccurrences(of: toReplace, with: replacement)
}
}