-(* not in Awodey *)
-Class PreMonoidalCat `(bc:BinoidalCat(C:=C))(I:C) :=
-{ pmon_I := I
-; pmon_bin := bc
-; pmon_cat := C
-; pmon_assoc : forall a b, (bin_second a >>>> bin_first b) <~~~> (bin_first b >>>> bin_second a)
-; pmon_cancelr : (bin_first I) <~~~> functor_id C
-; pmon_cancell : (bin_second I) <~~~> functor_id C
-; pmon_pentagon : Pentagon (fun a b c f => f ⋉ c) (fun a b c f => c ⋊ f) (fun a b c => #((pmon_assoc a c) b))
-; pmon_triangle : Triangle (fun a b c f => f ⋉ c) (fun a b c f => c ⋊ f) (fun a b c => #((pmon_assoc a c) b))
- (fun a => #(pmon_cancell a)) (fun a => #(pmon_cancelr a))
-; pmon_assoc_rr : forall a b, (bin_first (a⊗b)) <~~~> (bin_first a >>>> bin_first b)
-; pmon_assoc_ll : forall a b, (bin_second (a⊗b)) <~~~> (bin_second b >>>> bin_second a)
-; pmon_coherent_r : forall a c d:C, #(pmon_assoc_rr c d a) ~~ #(pmon_assoc a d c)⁻¹
-; pmon_coherent_l : forall a c d:C, #(pmon_assoc_ll c a d) ~~ #(pmon_assoc c d a)
-}.
-(*
- * Premonoidal categories actually have three associators (the "f"
- * indicates the position in which the operation is natural:
- *
- * assoc : (A ⋊ f) ⋉ C <-> A ⋊ (f ⋉ C)
- * assoc_rr : (f ⋉ B) ⋉ C <-> f ⋉ (B ⊗ C)
- * assoc_ll : (A ⋊ B) ⋊ f <-> (A ⊗ B) ⋊ f
- *
- * Fortunately, in a monoidal category these are all the same natural
- * isomorphism (and in any case -- monoidal or not -- the objects in
- * the left column are all the same and the objects in the right
- * column are all the same). This formalization assumes that is the
- * case even for premonoidal categories with non-central maps, in
- * order to keep the complexity manageable. I don't know much about
- * the consequences of having them and letting them be different; you
- * might need extra versions of the triangle/pentagon diagrams.
- *)
-
-Implicit Arguments pmon_cancell [ Ob Hom C bin_obj' bc I ].
-Implicit Arguments pmon_cancelr [ Ob Hom C bin_obj' bc I ].
-Implicit Arguments pmon_assoc [ Ob Hom C bin_obj' bc I ].
-Coercion pmon_bin : PreMonoidalCat >-> BinoidalCat.
-
-(* this turns out to be Exercise VII.1.1 from Mac Lane's CWM *)
-Lemma MacLane_ex_VII_1_1 `{mn:PreMonoidalCat(I:=EI)} a b
- : #((pmon_cancelr mn) (a ⊗ b)) ~~ #((pmon_assoc mn a EI) b) >>> (a ⋊-) \ #((pmon_cancelr mn) b).
- set (pmon_pentagon EI EI a b) as penta. unfold pmon_pentagon in penta.
- set (pmon_triangle a b) as tria. unfold pmon_triangle in tria.
- apply (fmor_respects(bin_second EI)) in tria.
- set (@fmor_preserves_comp) as fpc.
- setoid_rewrite <- fpc in tria.
- set (ni_commutes (pmon_assoc mn a b)) as xx.
- (* FIXME *)
- Admitted.
-
-(* Formalized Definition 3.10 *)
-Class PreMonoidalFunctor
-`(PM1:PreMonoidalCat(C:=C1)(I:=I1))
-`(PM2:PreMonoidalCat(C:=C2)(I:=I2))
- (fobj : C1 -> C2 ) :=
-{ mf_F :> Functor C1 C2 fobj
-; mf_preserves_i : mf_F I1 ≅ I2
-; mf_preserves_first : forall a, bin_first a >>>> mf_F <~~~> mf_F >>>> bin_first (mf_F a)
-; mf_preserves_second : forall a, bin_second a >>>> mf_F <~~~> mf_F >>>> bin_second (mf_F a)
-; mf_preserves_center : forall `(f:a~>b), CentralMorphism f -> CentralMorphism (mf_F \ f)
-}.
-Coercion mf_F : PreMonoidalFunctor >-> Functor.
-
-(*******************************************************************************)
-(* Braided and Symmetric Categories *)
-
-Class BraidedCat `(mc:PreMonoidalCat) :=
-{ br_niso : forall a, bin_first a <~~~> bin_second a
-; br_swap := fun a b => ni_iso (br_niso b) a
-; triangleb : forall a:C, #(pmon_cancelr mc a) ~~ #(br_swap a (pmon_I(PreMonoidalCat:=mc))) >>> #(pmon_cancell mc a)
-; hexagon1 : forall {a b c}, #(pmon_assoc mc _ _ _) >>> #(br_swap a _) >>> #(pmon_assoc mc _ _ _)
- ~~ #(br_swap _ _) ⋉ c >>> #(pmon_assoc mc _ _ _) >>> b ⋊ #(br_swap _ _)
-; hexagon2 : forall {a b c}, #(pmon_assoc mc _ _ _)⁻¹ >>> #(br_swap _ c) >>> #(pmon_assoc mc _ _ _)⁻¹
- ~~ a ⋊ #(br_swap _ _) >>> #(pmon_assoc mc _ _ _)⁻¹ >>> #(br_swap _ _) ⋉ b
-}.