LinkML slot inheritance in case of attributes

[uermel]

Hi all, I have a question regarding slot inheritance when using class attributes.

I'm trying to re-use a slot definition in the context of a class by specifying the parent slot in the attribute's is_a, but this doesn't seem to work when using the generators. I know there is slot_usage, but I'd like to change the slot name. I could define the slot outside of the class, but this would cause name collisions in the schema, which is why I'd prefer to define attributes instead.

Is this intended behavior, or should inheritance work when using is_a inside class attribute definitions?

Example schema:

id: id
name: example
prefixes:
  linkml: https://w3id.org/linkml/
default_range: string
default_prefix: ex

slots:
  integer_slot:
    range: integer

  a_derived_slot:
    is_a: integer_slot

classes:
  SampleClass:
    slots:
      - integer_slot
      - a_derived_slot
    attributes:
      another_derived_slot:
        is_a: integer_slot

Example when materialized with gen-linkml

name: example
id: id
prefixes:
  linkml:
    prefix_prefix: linkml
    prefix_reference: https://w3id.org/linkml/
default_prefix: ex
default_range: string
slots:
  integer_slot:
    name: integer_slot
    from_schema: id
    domain_of:
    - SampleClass
    range: integer
  a_derived_slot:
    name: a_derived_slot
    from_schema: id
    is_a: integer_slot
    domain_of:
    - SampleClass
classes:
  SampleClass:
    name: SampleClass
    from_schema: id
    slots:
    - integer_slot
    - a_derived_slot
    attributes:
      another_derived_slot:
        name: another_derived_slot
        from_schema: id
        is_a: integer_slot
        alias: another_derived_slot
        owner: SampleClass
        domain_of:
        - SampleClass
        range: string     # <-- range is default range, not the parent slot's range
      integer_slot:
        name: integer_slot
        from_schema: id
        alias: integer_slot
        owner: SampleClass
        domain_of:
        - SampleClass
        range: integer
      a_derived_slot:
        name: a_derived_slot
        from_schema: id
        is_a: integer_slot
        alias: a_derived_slot
        owner: SampleClass
        domain_of:
        - SampleClass
        range: integer  # <-- range is correct when inheriting outside the class context

[cmungall]

On reflection, I think we should have explicitly forbidden using is_a with attributes. It's intended use are for slots as first-class standalone entities. Attributes are meant to be for simpler self-contained cases. There are gaps in the documentation in what happens in your case and other unusual edge cases such as what happens if you try and inherit from an attribute of a parent class.

Having said that, the least surprising behavior would be to use the parent slot's range.

[uermel]

Thank you, I figured I was exploiting some unintended functionality. Is there an intended way to re-use slot definitions, but only within the context of a class (i.e. rename a slot in the context of a class)?