if (std::strlen(theOp) == 1)
  {
    // Try converting to integer
    Standard_Integer iOp = Draw::Atoi(theOp);
    if (iOp < 0 || iOp > 4)
    {
      // out of range
      return BOPAlgo_UNKNOWN;
    }

    // Check if satisfies the enumeration. If 0 is returned, check that 0 was really meant.
    if ((iOp > 0 && iOp <= 4) || (iOp == 0 && theOp[0] == '0'))
    {
      return static_cast<BOPAlgo_Operation>(iOp);
    }

    return BOPAlgo_UNKNOWN;
  }

  if (std::strlen(theOp) == 1)
  {
    if (theOp[0] >= '0' && theOp[0] <= '4'))
    {
      return static_cast<BOPAlgo_Operation>(theOp[0] - '0');
    }

    return BOPAlgo_UNKNOWN;
  }

  if (!strcasecmp(theOp, "common"))

+  theCommands.Add("bfillds", "Performs intersection of the arguments.\n"
+                  "\t\tUsage: bfillds [-t]\n"
+                  "\t\tWhere: -t is the optional parameter for enabling timer and showing elapsed time of the operation",
+                  __FILE__, bfillds, g);

+  Standard_EXPORT static BOPAlgo_Operation GetOperationType(const Standard_CString& theOp);