X-Git-Url: http://git.megacz.com/?p=coq-hetmet.git;a=blobdiff_plain;f=src%2FGeneralizedArrowCategory.v;h=3ec6660f533ba89eb5f19b227ac3486534db222c;hp=a9bedbb15ba3decb525f3826a1dc0fa359f09f68;hb=d2526b193694dd7a5c7ab9d80d6b6656a7459bb9;hpb=165690fe34fc2c88efa57cd2212db1ee324c4385 diff --git a/src/GeneralizedArrowCategory.v b/src/GeneralizedArrowCategory.v index a9bedbb..3ec6660 100644 --- a/src/GeneralizedArrowCategory.v +++ b/src/GeneralizedArrowCategory.v @@ -26,19 +26,36 @@ Require Import GeneralizedArrow. Require Import WeakFunctorCategory. Require Import SmallSMMEs. +(* + * Technically reifications form merely a *semicategory* (no identity + * maps), but one can always freely adjoin identity maps (and nothing + * else) to a semicategory to get a category whose non-identity-map + * portion is identical to the original semicategory + * + * Also, technically this category has ALL enrichments (not just the + * surjective monic monoidal ones), though there maps OUT OF only the + * surjective enrichments and INTO only the monic monoidal + * enrichments. It's a big pain to do this in Coq, but sort of might + * matter in real life: a language with really severe substructural + * restrictions might fail to be monoidally enriched, meaning we can't + * use it as a host language. But that's for the next paper... + *) Inductive GeneralizedArrowOrIdentity : SMMEs -> SMMEs -> Type := | gaoi_id : forall smme:SMMEs, GeneralizedArrowOrIdentity smme smme | gaoi_ga : forall s1 s2:SMMEs, GeneralizedArrow s1 s2 -> GeneralizedArrowOrIdentity s1 s2. -Definition generalizedArrowOrIdentityFunc - : forall s1 s2, GeneralizedArrowOrIdentity s1 s2 -> { fobj : _ & Functor s1 s2 fobj }. - intros. - destruct X. - exists (fun x => x). - apply functor_id. - eapply existT. - apply (g >>>> RepresentableFunctor s2 (mon_i s2)). - Defined. +Definition generalizedArrowOrIdentityFobj (s1 s2:SMMEs) (f:GeneralizedArrowOrIdentity s1 s2) : s1 -> s2 := + match f in GeneralizedArrowOrIdentity S1 S2 return S1 -> S2 with + | gaoi_id s => fun x => x + | gaoi_ga s1 s2 f => fun a => ehom(ECategory:=s2) (mon_i (smme_mon s2)) (ga_functor_obj f a) + end. + +Definition generalizedArrowOrIdentityFunc s1 s2 (f:GeneralizedArrowOrIdentity s1 s2) + : Functor s1 s2 (generalizedArrowOrIdentityFobj _ _ f) := + match f with + | gaoi_id s => functor_id _ + | gaoi_ga s1 s2 f => ga_functor f >>>> RepresentableFunctor s2 (mon_i s2) + end. Definition compose_generalizedArrows (s0 s1 s2:SMMEs) : GeneralizedArrow s0 s1 -> GeneralizedArrow s1 s2 -> GeneralizedArrow s0 s2. @@ -66,7 +83,7 @@ Definition generalizedArrowOrIdentityComp Definition MorphismsOfCategoryOfGeneralizedArrows : @SmallFunctors SMMEs. refine {| small_func := GeneralizedArrowOrIdentity ; small_func_id := fun s => gaoi_id s - ; small_func_func := fun smme1 smme2 f => projT2 (generalizedArrowOrIdentityFunc _ _ f) + ; small_func_func := fun smme1 smme2 f => generalizedArrowOrIdentityFunc _ _ f ; small_func_comp := generalizedArrowOrIdentityComp |}; intros; simpl. apply if_id.