changeset 431:a15f52456c78

clean up
author Shinji KONO <kono@ie.u-ryukyu.ac.jp>
date Sat, 26 Mar 2016 15:51:30 +0900
parents 46c057cb3d82
children 688066ac172e
files limit-to.agda maybeCat.agda
diffstat 2 files changed, 78 insertions(+), 78 deletions(-) [+]
line wrap: on
line diff
--- a/limit-to.agda	Sat Mar 26 15:47:46 2016 +0900
+++ b/limit-to.agda	Sat Mar 26 15:51:30 2016 +0900
@@ -16,9 +16,9 @@
 ---  two objects category
 ---
 ---          f
----       ------>
+---       -----→
 ---     0         1
----       ------>
+---       -----→
 ---          g
 
 
@@ -29,7 +29,7 @@
 
 -- constrainted arrow
 --    we need inverse of f to complete cases
-data Arrow {c₁ c₂ : Level } ( t00 t11 :  TwoObject {c₁} ) : TwoObject {c₁}  -> TwoObject {c₁} -> Set c₂ where
+data Arrow {c₁ c₂ : Level } ( t00 t11 :  TwoObject {c₁} ) : TwoObject {c₁}  → TwoObject {c₁} → Set c₂ where
    id-t0 : Arrow t00 t11 t00 t00
    id-t1 : Arrow t00 t11 t11 t11
    arrow-f :  Arrow t00 t11 t00 t11
@@ -45,7 +45,7 @@
 -- arrow composition
 
 
-comp :  ∀ {c₁  c₂}  -> {a b c : TwoObject {c₁}} →  Maybe ( Arrow {c₁} {c₂} t0 t1 b c ) →  Maybe ( Arrow {c₁} {c₂} t0 t1 a b )  →  Maybe ( Arrow {c₁} {c₂} t0 t1 a c )
+comp :  ∀ {c₁  c₂}  → {a b c : TwoObject {c₁}} →  Maybe ( Arrow {c₁} {c₂} t0 t1 b c ) →  Maybe ( Arrow {c₁} {c₂} t0 t1 a b )  →  Maybe ( Arrow {c₁} {c₂} t0 t1 a c )
 comp {_}  {_}  {_} {_} {_}  nothing     _                =   nothing 
 comp {_}  {_}  {_} {_} {_}  (just _     ) nothing          =   nothing 
 comp {_}  {_}  {t0} {t1} {t1}  (just id-t1 ) ( just arrow-f )  =   just arrow-f 
@@ -59,14 +59,14 @@
 comp {_}  {_}  {_} {_} {_}  (just _ ) ( just _ )  =   nothing 
 
 
-_×_ :  ∀ {c₁  c₂}  -> {a b c : TwoObject {c₁}} →  ( TwoHom {c₁}  {c₂} b c ) →  ( TwoHom {c₁} {c₂} a b )  →  ( TwoHom {c₁}  {c₂} a c )
+_×_ :  ∀ {c₁  c₂}  → {a b c : TwoObject {c₁}} →  ( TwoHom {c₁}  {c₂} b c ) →  ( TwoHom {c₁} {c₂} a b )  →  ( TwoHom {c₁}  {c₂} a c )
 _×_  {c₁}  {c₂}  {a} {b} {c} f g  = record { hom = comp  {c₁}  {c₂}  {a} {b} {c} (hom f) (hom g ) }
 
 
-_==_ :  ∀{ c₁ c₂ a b }   ->  Rel (Maybe (Arrow {c₁} {c₂} t0 t1 a b )) (c₂)
+_==_ :  ∀{ c₁ c₂ a b }   →  Rel (Maybe (Arrow {c₁} {c₂} t0 t1 a b )) (c₂)
 _==_   =  Eq   _≡_
 
-map2hom :  ∀{ c₁ c₂ } ->  {a b  : TwoObject {c₁}} →  Maybe ( Arrow  {c₁} {c₂} t0 t1 a b ) ->  TwoHom {c₁}  {c₂ } a b
+map2hom :  ∀{ c₁ c₂ } →  {a b  : TwoObject {c₁}} →  Maybe ( Arrow  {c₁} {c₂} t0 t1 a b ) →  TwoHom {c₁}  {c₂ } a b
 map2hom {_} {_} {t1} {t1} (just id-t1)  = record { hom =  just id-t1 }
 map2hom {_} {_} {t0} {t1} (just arrow-f) = record { hom =  just arrow-f }
 map2hom {_} {_} {t0} {t1} (just arrow-g) = record { hom =  just arrow-g }
@@ -80,21 +80,21 @@
 
 open TwoHom1
 
-==refl :  ∀{  c₁ c₂ a b }  ->  ∀ {x : Maybe (Arrow  {c₁} {c₂} t0 t1 a b )} → x == x
+==refl :  ∀{  c₁ c₂ a b }  →  ∀ {x : Maybe (Arrow  {c₁} {c₂} t0 t1 a b )} → x == x
 ==refl {_} {_} {_} {_} {just x}  = just refl
 ==refl {_} {_} {_} {_} {nothing} = nothing
 
-==sym :  ∀{  c₁ c₂ a b }   -> ∀ {x y :  Maybe (Arrow  {c₁}  {c₂} t0 t1 a b )} →  x == y →  y == x
+==sym :  ∀{  c₁ c₂ a b }   → ∀ {x y :  Maybe (Arrow  {c₁}  {c₂} t0 t1 a b )} →  x == y →  y == x
 ==sym (just x≈y) = just (≡-sym x≈y)
 ==sym nothing    = nothing
 
-==trans :  ∀{  c₁ c₂ a b }   -> ∀ {x y z :   Maybe (Arrow  {c₁}  {c₂} t0 t1 a b )  } →
+==trans :  ∀{  c₁ c₂ a b }   → ∀ {x y z :   Maybe (Arrow  {c₁}  {c₂} t0 t1 a b )  } →
          x == y → y == z  → x == z
 ==trans (just x≈y) (just y≈z) = just (≡-trans x≈y y≈z)
 ==trans nothing    nothing    = nothing
 
-==cong :  ∀{  c₁ c₂ a b c d }   -> ∀ {x y :  Maybe (Arrow  {c₁}  {c₂} t0 t1 a b )} →  
-        (f : Maybe (Arrow  {c₁}  {c₂} t0 t1 a b ) -> Maybe (Arrow  {c₁}  {c₂} t0 t1 c d ) ) -> x  ==  y →  f x == f y
+==cong :  ∀{  c₁ c₂ a b c d }   → ∀ {x y :  Maybe (Arrow  {c₁}  {c₂} t0 t1 a b )} →  
+        (f : Maybe (Arrow  {c₁}  {c₂} t0 t1 a b ) → Maybe (Arrow  {c₁}  {c₂} t0 t1 c d ) ) → x  ==  y →  f x == f y
 ==cong   {  c₁} {c₂} {a} {b } {c} {d} {nothing} {nothing} f nothing = ==refl
 ==cong   {  c₁} {c₂} {a} {b } {c} {d} {just x} {just .x} f (just refl)  = ==refl
 
@@ -223,7 +223,7 @@
 
 
 
-TwoId :  {c₁  c₂ : Level } (a : TwoObject  {c₁} ) ->  (TwoHom {c₁}  {c₂ } a a )
+TwoId :  {c₁  c₂ : Level } (a : TwoObject  {c₁} ) →  (TwoHom {c₁}  {c₂ } a a )
 TwoId {_} {_} t0 = record { hom =  just id-t0 }
 TwoId {_} {_} t1 = record { hom =  just id-t1 }
 
@@ -237,19 +237,19 @@
 --                ∎
 
 open import Relation.Binary
-TwoCat : {c₁ c₂ ℓ : Level  } ->  Category   c₁  c₂  c₂
+TwoCat : {c₁ c₂ ℓ : Level  } →  Category   c₁  c₂  c₂
 TwoCat   {c₁}  {c₂} {ℓ} = record {
     Obj  = TwoObject  {c₁} ;
     Hom = λ a b →    ( TwoHom {c₁}  {c₂ } a b ) ;
-    _o_ =  \{a} {b} {c} x y -> _×_ {c₁ } { c₂} {a} {b} {c} x y ;
-    _≈_ =  \x y -> hom x == hom y ;
-    Id  =  \{a} -> TwoId {c₁ } { c₂} a ;
+    _o_ =  λ{a} {b} {c} x y → _×_ {c₁ } { c₂} {a} {b} {c} x y ;
+    _≈_ =  λ x y → hom x == hom y ;
+    Id  =  λ{a} → TwoId {c₁ } { c₂} a ;
     isCategory  = record {
             isEquivalence =  record {refl = ==refl ; trans = ==trans ; sym = ==sym } ;
-            identityL  = \{a b f} -> identityL {c₁}  {c₂ } {a} {b} {f} ;
-            identityR  = \{a b f} -> identityR {c₁}  {c₂ } {a} {b} {f} ;
-            o-resp-≈  = \{a b c f g h i} ->  o-resp-≈  {c₁}  {c₂ } {a} {b} {c} {f} {g} {h} {i} ;
-            associative  = \{a b c d f g h } -> assoc-×   {c₁}  {c₂} {a} {b} {c} {d} {f} {g} {h}
+            identityL  = λ{a b f} → identityL {c₁}  {c₂ } {a} {b} {f} ;
+            identityR  = λ{a b f} → identityR {c₁}  {c₂ } {a} {b} {f} ;
+            o-resp-≈  = λ{a b c f g h i} →  o-resp-≈  {c₁}  {c₂ } {a} {b} {c} {f} {g} {h} {i} ;
+            associative  = λ{a b c d f g h } → assoc-×   {c₁}  {c₂} {a} {b} {c} {d} {f} {g} {h}
        }
    }  where
         identityL :  {c₁  c₂ : Level } {A B : TwoObject {c₁}} {f : ( TwoHom {c₁}  {c₂ } A B) } →  hom ((TwoId B)  × f)  == hom f
@@ -281,9 +281,9 @@
                     hom ( h × f )
                 ==⟨⟩
                     comp (hom h) (hom f)
-                ==⟨ ==cong (\ x  -> comp ( hom h ) x )  f==g ⟩
+                ==⟨ ==cong (λ x  → comp ( hom h ) x )  f==g ⟩
                     comp (hom h) (hom g)
-                ==⟨ ==cong (\ x  -> comp x ( hom g ) )  h==i ⟩
+                ==⟨ ==cong (λ x  → comp x ( hom g ) )  h==i ⟩
                     comp (hom i) (hom g)
                 ==⟨⟩
                     hom ( i × g )
@@ -291,31 +291,31 @@
 
 record  Nil {c₁ c₂ ℓ : Level} (A : Category c₁ c₂ ℓ)  :  Set   ( c₁ ⊔ c₂ ⊔ ℓ ) where
      field 
-         nil : {a b : Obj A } -> Hom A a b
-         nil-id : {a  : Obj A } ->  A [ nil {a} {a} ≈ id1 A a ]
-         nil-idL : {a b c : Obj A } -> { f : Hom A a b } -> A [ A [ nil {b} {c} o f ]   ≈ nil {a} {c} ]
-         nil-idR : {a b c : Obj A } -> { f : Hom A b c } -> A [ A [ f o nil {a} {b} ]   ≈ nil {a} {c} ]
+         nil : {a b : Obj A } → Hom A a b
+         nil-id : {a  : Obj A } →  A [ nil {a} {a} ≈ id1 A a ]
+         nil-idL : {a b c : Obj A } → { f : Hom A a b } → A [ A [ nil {b} {c} o f ]   ≈ nil {a} {c} ]
+         nil-idR : {a b c : Obj A } → { f : Hom A b c } → A [ A [ f o nil {a} {b} ]   ≈ nil {a} {c} ]
 
 open Nil
 
-justFunctor :  {c₁ c₂ ℓ : Level} (A : Category c₁ c₂ ℓ) ->  Nil A -> Functor  (MaybeCat A ) A
+justFunctor :  {c₁ c₂ ℓ : Level} (A : Category c₁ c₂ ℓ) →  Nil A → Functor  (MaybeCat A ) A
 justFunctor{c₁} {c₂} {ℓ} A none =  record {
          FObj = λ a → fobj a
        ; FMap = λ {a} {b} f → fmap {a} {b} f
        ; isFunctor = record {
-             identity = \{x} -> identity {x}
-             ; distr = \ {a} {b} {c} {f} {g}   -> distr2 {a} {b} {c} {f} {g}
-             ; ≈-cong = \ {a} {b} {c} {f}   -> ≈-cong  {a} {b} {c} {f}
+             identity = λ{x} → identity {x}
+             ; distr = λ {a} {b} {c} {f} {g}   → distr2 {a} {b} {c} {f} {g}
+             ; ≈-cong = λ {a} {b} {c} {f}   → ≈-cong  {a} {b} {c} {f}
        }
       } where
           MA = MaybeCat A
-          fobj :  Obj MA -> Obj A
-          fobj = \x -> x
-          fmap :  {x y : Obj MA } ->  Hom MA x y -> Hom A x y 
+          fobj :  Obj MA → Obj A
+          fobj = λ x → x
+          fmap :  {x y : Obj MA } →  Hom MA x y → Hom A x y 
           fmap {x} {y} f with MaybeHom.hom f
           fmap {x} {y} _ | nothing =  nil none
           fmap {x} {y} _ | (just f)  = f
-          identity  : {x : Obj MA} -> A [ fmap (id1 MA  x) ≈ id1 A (fobj x) ]
+          identity  : {x : Obj MA} → A [ fmap (id1 MA  x) ≈ id1 A (fobj x) ]
           identity  =  let open ≈-Reasoning (A) in  refl-hom
           distr2 :  {a : Obj MA} {b : Obj MA} {c : Obj MA} {f : Hom MA a b} {g : Hom MA b c} → A [ fmap (MA [ g o f ]) ≈ A [ fmap g o fmap f ] ]
           distr2 {a} {b} {c} {f} {g} with MaybeHom.hom f  | MaybeHom.hom g
@@ -329,21 +329,21 @@
           ≈-cong {a} {b} {f} {g} (just eq) | just _ | just _ = eq
 
 
-indexFunctor :  {c₁ c₂ ℓ : Level} (A : Category c₁ c₂ ℓ) (none : Nil A) ( a b : Obj A) ( f g : Hom A a b ) ->  Functor (TwoCat {c₁} {c₂} {c₂} ) A
+indexFunctor :  {c₁ c₂ ℓ : Level} (A : Category c₁ c₂ ℓ) (none : Nil A) ( a b : Obj A) ( f g : Hom A a b ) →  Functor (TwoCat {c₁} {c₂} {c₂} ) A
 indexFunctor  {c₁} {c₂} {ℓ} A none a b f g = record {
          FObj = λ a → fobj a
        ; FMap = λ {a} {b} f → fmap {a} {b} f
        ; isFunctor = record {
-             identity = \{x} -> identity {x}
-             ; distr = \ {a} {b} {c} {f} {g}   -> distr1 {a} {b} {c} {f} {g}
-             ; ≈-cong = \ {a} {b} {c} {f}   -> ≈-cong  {a} {b} {c} {f}
+             identity = λ{x} → identity {x}
+             ; distr = λ {a} {b} {c} {f} {g}   → distr1 {a} {b} {c} {f} {g}
+             ; ≈-cong = λ {a} {b} {c} {f}   → ≈-cong  {a} {b} {c} {f}
        }
       } where
           I = TwoCat  {c₁} {c₂} {ℓ}
-          fobj :  Obj I -> Obj A
+          fobj :  Obj I → Obj A
           fobj t0 = a
           fobj t1 = b
-          fmap :  {x y : Obj I } ->  (TwoHom {c₁}  {c₂} x y  ) -> Hom A (fobj x) (fobj y)
+          fmap :  {x y : Obj I } →  (TwoHom {c₁}  {c₂} x y  ) → Hom A (fobj x) (fobj y)
           fmap  {x} {y} h with hom h
           fmap  {t0} {t0} h | just id-t0 = id1 A a
           fmap  {t1} {t1} h | just id-t1 = id1 A b
@@ -412,27 +412,27 @@
 
 ---  Equalizer
 ---                     f
----          e       ------>
----     c ------>  a         b
----     ^      /     ------>
+---          e       -----→
+---     c -----→  a         b
+---     ^      /     -----→
 ---     |k   h          g
 ---     |   /
 ---     |  /            ^
 ---     | /             |
 ---     |/              | Γ
 ---     d _             |
----      |\             |
----        \ K          af
----         \        ------>
----          \     t0        t1
----                  ------>
+---      |λ             |
+---        λ K          af
+---         λ        -----→
+---          λ     t0        t1
+---                  -----→
 ---                     ag
 ---      
 ---      
 
 open Limit
 
-I' :  {c₁ c₂ ℓ : Level} ->  Category   c₁  c₂  c₂
+I' :  {c₁ c₂ ℓ : Level} →  Category   c₁  c₂  c₂
 I' {c₁} {c₂} {ℓ} = TwoCat {c₁} {c₂} {ℓ}
 
 lim-to-equ :  {c₁ c₂ ℓ : Level} (A : Category c₁ c₂ ℓ)  ( none : Nil A )
@@ -451,11 +451,11 @@
          I = I'   {c₁} {c₂} {ℓ} 
          Γ : Functor I A
          Γ = indexFunctor  {c₁} {c₂} {ℓ} A  none a b f g
-         nmap :  (x : Obj I ) ( d : Obj (A)  ) (h : Hom A d a ) -> Hom A (FObj (K A I d) x) (FObj Γ x)
+         nmap :  (x : Obj I ) ( d : Obj (A)  ) (h : Hom A d a ) → Hom A (FObj (K A I d) x) (FObj Γ x)
          nmap x d h with x 
          ... | t0 = h
-         ... | t1 =  A [ f o  h ] 
-         commute1 : {x y : Obj I}  {f' : Hom I x y} (d : Obj A) (h : Hom A d a ) ->  A [ A [ f  o  h ] ≈ A [ g  o h ] ]
+         ... | t1 = A [ f o  h ] 
+         commute1 : {x y : Obj I}  {f' : Hom I x y} (d : Obj A) (h : Hom A d a ) →  A [ A [ f  o  h ] ≈ A [ g  o h ] ]
                  → A [ A [ FMap Γ f' o nmap x d h ] ≈ A [ nmap y d h o FMap (K A I d) f' ] ]
          commute1  {x} {y} {f'}  d h fh=gh with hom f'
          commute1  {t0} {t0} {f'}  d h fh=gh | nothing = begin
@@ -543,19 +543,19 @@
          nat1 d h fh=gh = record {
             TMap = λ x → nmap x d h ;
             isNTrans = record {
-                commute = λ {x} {y} {f'} -> commute1 {x} {y} {f'} d h fh=gh 
+                commute = λ {x} {y} {f'} → commute1 {x} {y} {f'} d h fh=gh 
             }
           }
          eqlim = lim Γ  {c} {nat1 c e fe=ge }
          k : {d : Obj A}  (h : Hom A d a) → A [ A [ f  o  h ] ≈ A [ g  o h ] ] → Hom A d c
          k {d} h fh=gh  = limit eqlim d (nat1 d h fh=gh ) 
-         ek=h :  (d : Obj A ) (h : Hom A d a ) ->  ( fh=gh : A [ A [ f  o  h ] ≈ A [ g  o h ] ] )  -> A [ A [ e o k h fh=gh ] ≈ h ]
+         ek=h :  (d : Obj A ) (h : Hom A d a ) →  ( fh=gh : A [ A [ f  o  h ] ≈ A [ g  o h ] ] )  → A [ A [ e o k h fh=gh ] ≈ h ]
          ek=h d h fh=gh =   begin
                     e o k h fh=gh
                 ≈⟨ t0f=t eqlim {d} {nat1 d h fh=gh} {t0}  ⟩
                     h

-         uniq-nat :  {i : Obj I} →  (d : Obj A )  (h : Hom A d a ) ( k' : Hom A d c ) -> A [ A [ e o k' ] ≈ h ] -> A [ A [ nmap i c e o k' ] ≈ nmap i d h ]
+         uniq-nat :  {i : Obj I} →  (d : Obj A )  (h : Hom A d a ) ( k' : Hom A d c ) → A [ A [ e o k' ] ≈ h ] → A [ A [ nmap i c e o k' ] ≈ nmap i d h ]
          uniq-nat {t0} d h k' ek'=h =  begin
                     nmap t0 c e o k'
                 ≈⟨⟩
@@ -576,12 +576,12 @@
                 ≈⟨⟩
                     nmap t1 d h

-         uniquness :  (d : Obj A ) (h : Hom A d a ) ->  ( fh=gh : A [ A [ f  o  h ] ≈ A [ g  o h ] ] )  ->
+         uniquness :  (d : Obj A ) (h : Hom A d a ) →  ( fh=gh : A [ A [ f  o  h ] ≈ A [ g  o h ] ] )  →
                  ( k' : Hom A d c )
-                -> A [ A [ e o k' ] ≈ h ] → A [ k h fh=gh ≈ k' ]
+                → A [ A [ e o k' ] ≈ h ] → A [ k h fh=gh ≈ k' ]
          uniquness d h fh=gh k' ek'=h =   begin
                     k h fh=gh
-                ≈⟨ limit-uniqueness eqlim {d} {nat1 d h fh=gh } {k'} ( \{i} -> uniq-nat {i} d h k' ek'=h ) ⟩
+                ≈⟨ limit-uniqueness eqlim {d} {nat1 d h fh=gh } {k'} ( λ{i} → uniq-nat {i} d h k' ek'=h ) ⟩
                     k'

 
--- a/maybeCat.agda	Sat Mar 26 15:47:46 2016 +0900
+++ b/maybeCat.agda	Sat Mar 26 15:51:30 2016 +0900
@@ -18,16 +18,16 @@
 
 open MaybeHom
 
-_+_ :  { c₁ c₂ ℓ : Level} -> { A : Category c₁ c₂ ℓ } ->  {a b c : Obj A } → MaybeHom A b c  →  MaybeHom A a b  →  MaybeHom A  a c 
+_+_ :  { c₁ c₂ ℓ : Level} → { A : Category c₁ c₂ ℓ } →  {a b c : Obj A } → MaybeHom A b c  →  MaybeHom A a b  →  MaybeHom A  a c 
 _+_  {x} {y} {z} {A} {a} {b} {c} f g with hom f | hom g
 _+_  {_} {_} {_} {A} {a} {b} {c} f g | nothing  | _  = record { hom =  nothing }
 _+_  {_} {_} {_} {A} {a} {b} {c} f g | _ | nothing   = record { hom =  nothing }
 _+_  {_} {_} {_} {A} {a} {b} {c} _ _ | (just f) |  (just g)  = record { hom =  just ( A [ f o  g ]  ) }
 
-MaybeHomId  : { c₁ c₂ ℓ : Level} { A : Category c₁ c₂ ℓ } (a  : Obj A ) -> MaybeHom A a a
+MaybeHomId  : { c₁ c₂ ℓ : Level} { A : Category c₁ c₂ ℓ } (a  : Obj A ) → MaybeHom A a a
 MaybeHomId   {_} {_} {_} {A} a  = record { hom = just ( id1 A a)  }
 
-_[_≡≡_] : { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ )  {a b : Obj A } ->  Rel (Maybe (Hom A a b)) (c₂ ⊔ ℓ) 
+_[_≡≡_] : { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ )  {a b : Obj A } →  Rel (Maybe (Hom A a b)) (c₂ ⊔ ℓ) 
 _[_≡≡_]  A =  Eq ( Category._≈_ A ) 
 
 
@@ -37,20 +37,20 @@
         infixr 2 _≡≡⟨_⟩_ _≡≡⟨⟩_
         infix  1 begin_
 
-        ≡≡-refl :   {a b : Obj A } -> {x : Maybe ( Hom A a b ) } → A [ x ≡≡ x ]
+        ≡≡-refl :   {a b : Obj A } → {x : Maybe ( Hom A a b ) } → A [ x ≡≡ x ]
         ≡≡-refl  {_} {_} {just x}  = just refl-hom where  open ≈-Reasoning (A)
         ≡≡-refl  {_} {_} {nothing} = nothing
 
-        ≡≡-sym :  {a b : Obj A } -> {x y : Maybe ( Hom A a b ) }  → A [ x ≡≡ y ] → A [ y ≡≡ x ]
+        ≡≡-sym :  {a b : Obj A } → {x y : Maybe ( Hom A a b ) }  → A [ x ≡≡ y ] → A [ y ≡≡ x ]
         ≡≡-sym (just x≈y) = just (sym x≈y)  where  open ≈-Reasoning (A)
         ≡≡-sym nothing    = nothing
 
-        ≡≡-trans :  {a b : Obj A } -> {x y z : Maybe ( Hom A a b ) }  → A [ x ≡≡ y ] → A [ y ≡≡ z ] → A [ x ≡≡ z ]
+        ≡≡-trans :  {a b : Obj A } → {x y z : Maybe ( Hom A a b ) }  → A [ x ≡≡ y ] → A [ y ≡≡ z ] → A [ x ≡≡ z ]
         ≡≡-trans (just x≈y) (just y≈z) = just (trans-hom x≈y y≈z)  where  open ≈-Reasoning (A)
         ≡≡-trans nothing    nothing    = nothing
 
-        ≡≡-cong :  ∀{ a b c d }   -> ∀ {x y :  Maybe (Hom A a b )} →
-                (f : Maybe (Hom A a b ) -> Maybe (Hom A c d ) )  ->  x  ≡  y  →  A [ f x ≡≡ f y ]
+        ≡≡-cong :  ∀{ a b c d }   → ∀ {x y :  Maybe (Hom A a b )} →
+                (f : Maybe (Hom A a b ) → Maybe (Hom A c d ) )  →  x  ≡  y  →  A [ f x ≡≡ f y ]
         ≡≡-cong  {a} {b } {c} {d} {nothing} {nothing} f refl  = ≡≡-refl
         ≡≡-cong  {a} {b } {c} {d} {just x} {just .x} f refl  = ≡≡-refl
 
@@ -76,27 +76,27 @@
 
 
 
-MaybeCat : { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ ) -> Category   c₁ (ℓ ⊔ c₂)  (ℓ ⊔ c₂)
+MaybeCat : { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ ) → Category   c₁ (ℓ ⊔ c₂)  (ℓ ⊔ c₂)
 MaybeCat { c₁} {c₂} {ℓ} ( A ) =   record {
     Obj  = Obj A  ;
     Hom = λ a b →   MaybeHom A  a b   ; 
     _o_ =  _+_   ;
     _≈_ = λ a b →    _[_≡≡_] { c₁} {c₂} {ℓ} A  (hom a) (hom b)  ;
-    Id  =  \{a} -> MaybeHomId a ;
+    Id  =  λ {a} → MaybeHomId a ;
     isCategory  = record {
             isEquivalence = let open ≡≡-Reasoning (A) in record {refl = ≡≡-refl ; trans = ≡≡-trans ; sym = ≡≡-sym  } ;
-            identityL  = \{a b f} -> identityL {a} {b} {f} ;
-            identityR  = \{a b f} -> identityR {a} {b} {f};
-            o-resp-≈  = \{a b c f g h i} ->  o-resp-≈ {a} {b} {c} {f} {g} {h} {i} ;
-            associative  = \{a b c d f g h } -> associative {a } { b } { c } { d } { f } { g } { h }
+            identityL  = λ {a b f} → identityL {a} {b} {f} ;
+            identityR  = λ {a b f} → identityR {a} {b} {f};
+            o-resp-≈  = λ {a b c f g h i} →  o-resp-≈ {a} {b} {c} {f} {g} {h} {i} ;
+            associative  = λ {a b c d f g h } → associative {a } { b } { c } { d } { f } { g } { h }
        } 
    } where
-        identityL : { a b : Obj A } { f : MaybeHom A a b } ->  A [ hom (MaybeHomId b + f) ≡≡ hom f ]
+        identityL : { a b : Obj A } { f : MaybeHom A a b } →  A [ hom (MaybeHomId b + f) ≡≡ hom f ]
         identityL {a} {b} {f}  with hom f
         identityL {a} {b} {_} | nothing  = nothing
         identityL {a} {b} {_} | just f = just ( IsCategory.identityL ( Category.isCategory A )  {a} {b} {f}  )
 
-        identityR : { a b : Obj A } { f : MaybeHom A a b } ->  A [ hom (f + MaybeHomId a  ) ≡≡ hom f ]
+        identityR : { a b : Obj A } { f : MaybeHom A a b } →  A [ hom (f + MaybeHomId a  ) ≡≡ hom f ]
         identityR {a} {b} {f}  with hom f
         identityR {a} {b} {_} | nothing  = nothing
         identityR {a} {b} {_} | just f = just ( IsCategory.identityR ( Category.isCategory A )  {a} {b} {f}  )
@@ -120,7 +120,7 @@
         associative  {a} {b} {c} {d} {_} {_} {_}  | just f | just g | just h = 
              just ( IsCategory.associative ( Category.isCategory A )  {a} {b} {c} {d} {f} {g} {h}  )
 
-≈-to-== : { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ ) ->  { a b :  Obj A }
-    { f g : Hom A a b } ->
-    A [ f ≈ g ] -> (MaybeCat A) [  record { hom = just f } ≈  record { hom = just g } ]
+≈-to-== : { c₁ c₂ ℓ : Level} ( A : Category c₁ c₂ ℓ ) →  { a b :  Obj A }
+    { f g : Hom A a b } →
+    A [ f ≈ g ] → (MaybeCat A) [  record { hom = just f } ≈  record { hom = just g } ]
 ≈-to-==  A {a} {b} {f} {g} f≈g =  just f≈g