import Foundation
let pattern = #"(?:(\d+-)((?:\d+~\d+|(?:,?\s*\d+){2,})+)(?=,\s*\d+-|\"))"#
let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines)
let testString = #"""
sample_string1 = "376-12~23, 28, 32, 35, 37,376-1"
sample_string2 = "391-1~8, 391-22~23"
sample_string3 = "391-10~21, 391-24, 27, 29"
"""#
let stringRange = NSRange(location: 0, length: testString.utf16.count)
let substitutionString = #"\1(\2)"#
let result = regex.stringByReplacingMatches(in: testString, range: stringRange, withTemplate: substitutionString)
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