docs: function captureLine() {
      if (!hasStacks) {
          return;
      }
  
      try {
          throw new Error();
      } catch (e) {
          var lines = e.stack.split("\n");
          var firstLine = lines[0].indexOf("@") > 0 ? lines[1] : lines[2];
          var fileNameAndLineNumber = getFileNameAndLineNumber(firstLine);
          if (!fileNameAndLineNumber) {
              return;
          }
  
          qFileName = fileNameAndLineNumber[0];
          return fileNameAndLineNumber[1];
      }
  }