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I original left out zero objects in PtdSetCategory and PtdSetSchema but now I want the Attr side to be allowed to have a zero object so that I can pull attrs out of a hat that aren't in the source schema; I'm not sure whether I really need the zero object in the combinatorial side yet but why tempt fate?

@AlgebraicJulia AlgebraicJulia deleted a comment from github-actions bot Sep 29, 2023
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Thanks for the PR. With the idea that Catlab.Theories should contain a hierarchy of plausibly useful theories even if we don't immediately need them, I might suggest having:

  1. ThPointedSetCategory for a category enriched in pointed sets, as before
  2. ThPointedCategory for a pointed category inherits from ThPointedSetCategory, adding the zero objects.

"""
@theory ThPointedSetCategory{Ob,Hom} <: ThCategory{Ob,Hom} begin
@theory ThPointedCategory{Ob,Hom} <: ThCategory{Ob,Hom} begin
ZeroOb()::Ob
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Our convention for term constructors in Catlab.Theories is that they are lowercase.

compose(g::(A→B),zeromap(A,B))==zeromap(A,C)(A::Ob,B::Ob,C::Ob)

#f == g ⊣ (A::Ob,f::Hom(A,ZeroOb()),g::Hom(A,ZeroOb()))
#f == g ⊣ (B::Ob,f::Hom(ZeroOb(),B),g::Hom(ZeroOb(),B))
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Why have commented out axioms?

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Documentation on your documentation.

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4 participants