Changes between Version 25 and Version 31 of Ticket #16340

Sep 11, 2014, 4:48:46 PM (8 years ago)
Travis Scrimshaw

Replying to pbruin:

Is it clear that the "structure category" terminology is the way to go? Personally I still don't like it very much (again, it pretends to be about categories but instead is about relations to their supercategories).

It's more of there has been no better alternative proposed. If we move away from the terminology "structure category", then I feel like we loose the ability to name methods like all_structure_super_categories. However I do understand your objection.

I would prefer the proposals made by Nicolas in comment:9 and Simon in comment:10 to have an additional_structure() method that returns something meaningful about the additional structure, not just True or False.

Currently the default is that new subcategories are structure categories (so they are not full subcategories). If we were to go with returning pairs (op, method), then the question becomes do we want the default to be False or do we allow True to remain the default and have it be when we can't adequately define the structure?

Actually, that made me have a thought. How about instead of is_structure_category we have has_additional_structure, and then we could extend this to additional_structure (on a followup ticket).


  • Ticket #16340

    • Property Reviewers changed from to Darij Grinberg, Travis Scrimshaw
    • Property Work issues changed from find good names to
    • Property Commit changed from 737a8f0c80a80040cb3c0308b1d2063f456662d0 to d4c7a88563a397291b6cd5ddadb8f574cc1eedb5
  • Ticket #16340 – Description

    v25 v31  
    4646(just take the union of the structure super categories of the super
    47 categories of ``self``, and add ``self`` if relevant).
     47categories of {{{``self``}}}, and add {{{``self``}}} if relevant).
    4949It is now trivial to check whether a subcategory B of A is actually a
    9999== Limitation ==
    101 The current model forces the following assumption: `C\subset B\subset
    102 A` is a chain of categories and `C` is a full subcategory of `A`, then
     101The current model forces the following assumption: `C \subset B \subset A` is a chain of categories and `C` is a full subcategory of `A`, then
    103102`C` is a full subcategory of `B` and `B` is a full subcategory of `A`.
    104103In particular, we can't model situations where, within the context of