import Foundation
let pattern = #"[^A-Z]+|(?:(?=[A-Za-z]*[a-z])\b[A-Za-z]+\b)|(?:\b[A-Z]+\b(?=[^a-z]+[A-Z])(?:[^a-z]*\b[A-Z]+\b)*\b)"#
let regex = try! NSRegularExpression(pattern: pattern)
let testString = #"""
This is a sentence WITH some capitalised WORDS
IN it AS well as
MULTILINING
"""#
let stringRange = NSRange(location: 0, length: testString.utf16.count)
let matches = regex.matches(in: testString, range: stringRange)
var result: [[String]] = []
for match in matches {
var groups: [String] = []
for rangeIndex in 1 ..< match.numberOfRanges {
let nsRange = match.range(at: rangeIndex)
guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue }
let string = (testString as NSString).substring(with: nsRange)
groups.append(string)
}
if !groups.isEmpty {
result.append(groups)
}
}
print(result)
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression