public String isValidOperand(FullArgument operand,boolean executeNow){
  if (operand.address.type == Op.ERROR) {
    return "Invalid Expression";
  }
  if ((operand.address.type & Op.MEM) != 0) {
    return isValidAddress(operand.arg,operand.address.size,executeNow);
  }
  return null;
}

public String isValidOperand ( FullArgument operand , boolean executeNow ) { if ( operand . address . type == Op . ERROR ) { return "Invalid Expression" ; } if ( ( operand . address . type & Op . MEM ) != 0 ) { return isValidAddress ( operand . arg , operand . address . size , executeNow ) ; } return null ; }
checks whether an operand is valid
