Back to previous SELECT transformation

[riemi-nie]

Citing the EXPRESS documentation (ISO-10303-11) page 34:

NOTE The value of a select data type may be a value of more than one of the named data types
specified in the select list for that select data type.

EXAMPLE 1 If a and b are subtypes of c, and if they are related by an andor expression, and if there
is a data type defined by SELECT (a,b), then it may be that the value of the select data type is an a
and a b at the same time.

EXAMPLE 2 A choice must be made among several types of things in a given context.

It seems like it is possible that a SELECT can hold multiple values of different types at runtime.
With an extended version of the previous mapping this should be possible.

@bekraft Did I totally misunderstood that?

[bekraft]

@riemi-nie No. But design time and runtime are mixed in EXPRESS.

These notes are related to the supertype rules of ANDOR and AND. Since these rules make only sense in the context of instances. Currently, both rules are not supported by XpressModel when generating Xcore. Only ONEOF is implicitly supported. At runtime a select can only refer to a single instance of a type or an entity, event though the pure value (i.e. numerical value) can refer to more than one type (i.e. INTEGER, NUMBER etc.).