import Foundation
let pattern = #"AND op.OP(\d{1,2})(OPVerfahren.*?\))"#
let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .dotMatchesLineSeparators])
let testString = #"""
AND op.OP1OPVerfahren > 0
AND p.Testzwecke = 0
AND NOT EXISTS (SELECT DISTINCT 1 FROM ods01.dat_optherapie op2 WHERE op2.patID = p.ID AND op2.revision > op.revision)
UNION ALL
AND op.OP2OPVerfahren > 0
AND p.Testzwecke = 0
AND NOT EXISTS (SELECT DISTINCT 1 FROM ods01.dat_optherapie op2 WHERE op2.patID = p.ID AND op2.revision > op.revision)
UNION ALL
"""#
let stringRange = NSRange(location: 0, length: testString.utf16.count)
let substitutionString = #"AND op.OP$1$2 \n GROUP BY OP$1OPVerfahren"#
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