如何使用Swift正则表达式捕获Unicode字符

Question

I have a String in Swift which looks as follows in the debugger of Xcode

Random Text: \\u{e2}specificText:

When I print the text in the console of Xcode it looks like

Random Text: ‎ specificText:

If I paste the text in question in some editor it looks like a bold dot.

Which regular expression do I have to use to just capture \\u{e2} in the above text? Which unicode character is that?

I am using the following String extension to get the captured groups:

extension String {
  func capturedGroups(forRegex regex: String) -> [String]? {
    guard let expression = try? NSRegularExpression(pattern: regex) else { return nil }
    let matches = expression.matches(in: self, options: [], range: NSRange(location:0, length: (self as NSString).count))
    guard let match = matches.first else { return nil }
    let lastRangeIndex = match.numberOfRanges - 1
    guard lastRangeIndex >= 1 else { return nil }
    var results = [String]()
    for i in 1...lastRangeIndex {
        let capturedGroupIndex = match.range(at: i)
        let matchedString = (self as NSString).substring(with: capturedGroupIndex)
        results.append(matchedString)
    }
    return results
  }
}

I have tried the following but it did not work

snippet.capturedGroups(forRegex: "(\\u00e2)")

Answer 1

I debugged the strings containing \\u{e2} with Xcode with the following code:

snippet.characters.forEach { character in
    print(character)
}

After setting a breakpoint at the print line I found out that although the Xcode debugger shows the following Unicode characters as \\u{e2} when looking at the string the characters which I was actually confronted with were

https://unicode-table.com/en/200E/

https://unicode-table.com/en/202A/

https://unicode-table.com/en/202C/

I could capture the unicode characters with the following code with my extension outlined in the question above:

snippet.capturedGroups(forRegex: "([\\u200E]{1})")
snippet.capturedGroups(forRegex: "([\\u202A]{1})")
snippet.capturedGroups(forRegex: "([\\u202C]{1})")