/*
   * @desc      restore URL-encoded (or "percent-encoded") URL:
   *            replace all "%XY" with the the respective character corresponding to the hex code XY
   * @param     p_EncodedUrl
   * @return    charstring
   * @status    APPROVED (IMS)
   */
  function f_URL_Decoding(charstring p_EncodedUrl) return charstring
  {
    var charstring v_Url := p_EncodedUrl;
    var charstring v_Pattern := "(*)(%[0-9a-fA-F]#2)*";  /* @sic R5s151006: * at the end sic@ */
    var charstring v_PercentCodedChar;
    var charstring v_HexCode;
    var charstring v_Char;
    var integer v_Pos;
    
    while (true) {
      v_PercentCodedChar := regexp(v_Url, v_Pattern, 1);
      if (v_PercentCodedChar != "") {
        v_Pos := lengthof(regexp(v_Url, v_Pattern, 0));
        v_HexCode := substr(v_PercentCodedChar, 1, 2);
        v_Char := oct2char(hex2oct(str2hex(v_HexCode)));
        v_Url := replace(v_Url, v_Pos, 3, v_Char);
      } else {
        break;
      }
    }
    return v_Url;
  }

2019/Nov/14 00:21:01.410332 DEBUG IMS_CommonDefs.ttcn:160 regexp(): POSIX ERE equivalent of pattern "(*)(%[0-9a-fA-F]#2)*" is: "^(.*)(%[0-9A-Fa-f]{2}).*$"