import Foundation
let pattern = #"(,\s(?:vol|pt)\.(*SKIP)(*F)|(?:vol|pt|volume|part))"#
let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .caseInsensitive])
let testString = #"""
Should Match:
a) Any occurences of "Volume" OR "Part" (Case Insensitive);
b) Any occurence of "vol" or "pt" (CI) that does not have [[comma][space] before AND [period] after;
My volume 1
My name vol2.
My, volume 1
, pt. vol2.
, part.
, pt.
, pt
, vol
. pt.
// Should match below as there is no [period] after it
The Red Pill, Pt 2
, Pt 2
"""#
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