inline op_iterator op_begin() { return Operands.begin(); }
inline const_op_iterator op_begin() const { return Operands.begin(); }
inline op_iterator op_end() { return Operands.end(); }
inline op_iterator op_begin() { return Operands.begin(); }
inline const_op_iterator op_begin() const { return Operands.begin(); }
inline op_iterator op_end() { return Operands.end(); }