     // Go through each arg and add arguments from response files.
     for arg in args {
       if arg.first == "@", let responseFile = try? AbsolutePath(validating: String(arg.dropFirst())) {
-        // Guard against infinity parsing loop.
+        // Guard against infinite parsing loop.
         guard visitedResponseFiles.insert(responseFile).inserted else {
           diagnosticsEngine.emit(.warn_recursive_response_file(responseFile))
           continue

  /// - Parameter content: response file's content to be tokenized.
  private static func tokenizeResponseFile(_ content: String) -> [String] {
    return content
      .split(separator: "\n")
      .map { tokenizeResponseFileLine($0) }
      .filter { !$0.isEmpty }
  }
  
  /// Recursively expands the response files.

  /// 2. Backslash escaping.
  /// 3. Space character (U+0020 SPACE).
  ///
  /// - Returns: One line String ready to be used in the shell, if any.
  ///
  /// - Complexity: O(*n*), where *n* is the length of the line.
  private static func tokenizeResponseFileLine<S: StringProtocol>(_ line: S) -> String? {
    if line.isEmpty { return nil }
    
    // Support double dash comments only if they start at the beginning of a line.
    if line.first == "/", line.count > 1, line[line.index(after: line.startIndex)] == "/" { return nil }
    
    var result: String = ""
    /// Indicates if we just parsed an escaping backslash.
