EXPRESS DAm -- A request from the Part 108 folk

[Lothar Klein]

Ed,

There is one occurrence of an attribute reference in part41
2nd edition, the attribute_value_assignment, see below.
For me the definition is very cumbersome and will lead to real
problems in cases of multiple inheritance with different attributes
but same names.
Actually this construct is used in AP214 for the multi-language string.

I'm in favor of a real solution of this problem.

Lothar

----------------


8.4.7 attribute_value_assignment
An attribute_value_assignment is an association of an additional value
to a string valued attribute of
an existing entity. The relationship of the additional value to the
existing attribute is determined by the
role. The entity that has the attribute for which an additional value is
specified is identified by
specializations of attribute_value_assignment.
EXPRESS specification
*)
ENTITY attribute_value_assignment
ABSTRACT SUPERTYPE;
attribute_name : label;
attribute_value : attribute_type;
role : attribute_value_role;
END_ENTITY; -- attribute_value_assignment
(*
Attribute definitions
attribute_name: the attribute for which the additional value is defined.
The attribute_name shall
identify an attribute of the assigned entity.
NOTE 1 The identified attribute may be defined in the entity or
inherited from a supertype.
EXAMPLE 'name' and 'description' are examples for the attribute_name.
attribute_value: the attribute_type that contains, as label, the
additional value for the attribute of the
assigned entity specified by attribute_name.
role: the attribute_value_role that specifies the purpose of the
association of the attribute_value_-assignment
with product data.
NOTE 2 The values related to this attribute can be specified in an
annotated EXPRESS schema that uses or
specializes this entity, or in an agreement of common understanding
between the partners sharing this information.
Informal propositions:
IP1: The type of attribute_value_assignment.attribute_value (label or
text) shall be the same as the
type of the attribute specified by
attribute_value_assignment.attribute_name.


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