message_conversion.py 文件源码

def _to_object_inst(msg, rostype, roottype, inst, stack):
    # Typecheck the msg
    if type(msg) is not dict:
        raise FieldTypeMismatchException(roottype, stack, rostype, type(msg))

    # Substitute the correct time if we're an std_msgs/Header
    if rostype in ros_header_types:
        inst.stamp = rospy.get_rostime()

    inst_fields = dict(zip(inst.__slots__, inst._slot_types))

    for field_name in msg:
        # Add this field to the field stack
        field_stack = stack + [field_name]

        # Raise an exception if the msg contains a bad field
        if not field_name in inst_fields:
            raise NonexistentFieldException(roottype, field_stack)

        field_rostype = inst_fields[field_name]
        field_inst = getattr(inst, field_name)

        field_value = _to_inst(msg[field_name], field_rostype,
                    roottype, field_inst, field_stack)

        setattr(inst, field_name, field_value)

    return inst