import Foundation
let pattern = #".*\.(\w{3,})$"#
let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .caseInsensitive])
let testString = ##"""
http://www.w3schools.com/jsref/jsref_regexp_exec.asp
https://translate.google.com/#en/pt/Thank%20you%20Engr!%20That%20is%20awesome.php
www.facebook.com/index.asp
"""##
let stringRange = NSRange(location: 0, length: testString.utf16.count)
let substitutionString = #"$1"#
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