# HG changeset patch
# User Shinji KONO <kono@ie.u-ryukyu.ac.jp>
# Date 1599958113 -32400
# Node ID c00eac825964dc3f2a666e0e3953fad4e4805caa
# Parent  5e5e6cd7da2ea107a33cec541f908a9e3504af94
FLutil

diff -r 5e5e6cd7da2e -r c00eac825964 FL.agda
--- a/FL.agda	Sun Sep 13 09:33:57 2020 +0900
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,165 +0,0 @@
-module FL where
-
-open import Level hiding ( suc ; zero )
-open import Data.Fin hiding ( _<_  ; _≤_ ; _-_ ; _+_ ; _≟_)
-open import Data.Fin.Properties hiding ( <-trans ; ≤-trans ; ≤-irrelevant ; _≟_ ) renaming ( <-cmp to <-fcmp )
-open import Data.Fin.Permutation
-open import Data.Nat -- using (ℕ; suc; zero; s≤s ; z≤n )
-open import Relation.Binary.PropositionalEquality 
-open import Data.List using (List; []; _∷_ ; length ; _++_ ; head ; tail ) renaming (reverse to rev )
-open import Data.Product
-open import Relation.Nullary
-open import Data.Empty
-open import  Relation.Binary.Core
-open import  Relation.Binary.Definitions
-open import logic
-open import nat
-
-infixr  100 _::_
-
-data  FL : (n : ℕ )→ Set where
-   f0 :  FL 0 
-   _::_ :  { n : ℕ } → Fin (suc n ) → FL n → FL (suc n)
-
-data _f<_  : {n : ℕ } (x : FL n ) (y : FL n)  → Set  where
-   f<n : {m : ℕ } {xn yn : Fin (suc m) } {xt yt : FL m} → xn Data.Fin.< yn →   (xn :: xt) f< ( yn :: yt )
-   f<t : {m : ℕ } {xn : Fin (suc m) } {xt yt : FL m} → xt f< yt →   (xn :: xt) f< ( xn :: yt )
-
-FLeq : {n : ℕ } {xn yn : Fin (suc n)} {x : FL n } {y : FL n}  → xn :: x ≡ yn :: y → ( xn ≡ yn )  × (x ≡ y )
-FLeq refl = refl , refl 
-
-f-<> :  {n : ℕ } {x : FL n } {y : FL n}  → x f< y → y f< x → ⊥
-f-<> (f<n x) (f<n x₁) = nat-<> x x₁
-f-<> (f<n x) (f<t lt2) = nat-≡< refl x
-f-<> (f<t lt) (f<n x) = nat-≡< refl x
-f-<> (f<t lt) (f<t lt2) = f-<> lt lt2
-
-f-≡< :  {n : ℕ } {x : FL n } {y : FL n}  → x ≡ y → y f< x → ⊥
-f-≡< refl (f<n x) = nat-≡< refl x
-f-≡< refl (f<t lt) = f-≡< refl lt 
-
-FLcmp : {n : ℕ } → Trichotomous {Level.zero} {FL n}  _≡_  _f<_
-FLcmp f0 f0 = tri≈ (λ ()) refl (λ ())
-FLcmp (xn :: xt) (yn :: yt) with <-fcmp xn yn
-... | tri< a ¬b ¬c = tri< (f<n a) (λ eq → nat-≡< (cong toℕ (proj₁ (FLeq eq)) ) a) (λ lt  → f-<> lt (f<n a) )
-... | tri> ¬a ¬b c = tri> (λ lt  → f-<> lt (f<n c) ) (λ eq → nat-≡< (cong toℕ (sym (proj₁ (FLeq eq)) )) c) (f<n c)
-... | tri≈ ¬a refl ¬c with FLcmp xt yt
-... | tri< a ¬b ¬c₁ = tri< (f<t a) (λ eq → ¬b (proj₂ (FLeq eq) )) (λ lt  → f-<> lt (f<t a) )
-... | tri≈ ¬a₁ refl ¬c₁ = tri≈ (λ lt → f-≡< refl lt )  refl (λ lt → f-≡< refl lt )
-... | tri> ¬a₁ ¬b c = tri> (λ lt  → f-<> lt (f<t c) ) (λ eq → ¬b (proj₂ (FLeq eq) )) (f<t c)
-
-f<-trans : {n : ℕ } { x y z : FL n } → x f< y → y f< z → x f< z
-f<-trans {suc n} (f<n x) (f<n x₁) = f<n ( Data.Fin.Properties.<-trans x x₁ )
-f<-trans {suc n} (f<n x) (f<t y<z) = f<n x
-f<-trans {suc n} (f<t x<y) (f<n x) = f<n x
-f<-trans {suc n} (f<t x<y) (f<t y<z) = f<t (f<-trans x<y y<z)
-
-infixr 250 _f<?_
-
-_f<?_ : {n  : ℕ} → (x y : FL n ) → Dec (x f< y )
-x f<? y with FLcmp x y
-... | tri< a ¬b ¬c = yes a
-... | tri≈ ¬a refl ¬c = no ( ¬a )
-... | tri> ¬a ¬b c = no ( ¬a )
-
-_f≤_ : {n : ℕ } (x : FL n ) (y : FL n)  → Set
-_f≤_ x y = (x ≡ y ) ∨  (x f< y )
-
-FL0 : {n : ℕ } → FL n
-FL0 {zero} = f0
-FL0 {suc n} = zero :: FL0
-
-
-fmax : { n : ℕ } →  FL n
-fmax {zero} = f0
-fmax {suc n} = fromℕ< a<sa :: fmax {n}
-
-fmax< : { n : ℕ } → {x : FL n } → ¬ (fmax f< x )
-fmax< {suc n} {x :: y} (f<n lt) = nat-≤> (fmax1 x) lt where
-    fmax1 : {n : ℕ } → (x : Fin (suc n)) → toℕ x ≤ toℕ (fromℕ< {n} a<sa)
-    fmax1 {zero} zero = z≤n
-    fmax1 {suc n} zero = z≤n
-    fmax1 {suc n} (suc x) = s≤s (fmax1 x) 
-fmax< {suc n} {x :: y} (f<t lt) = fmax< {n} {y} lt
-
-fmax¬ : { n : ℕ } → {x : FL n } → ¬ ( x ≡ fmax ) → x f< fmax
-fmax¬ {zero} {f0} ne = ⊥-elim ( ne refl ) 
-fmax¬ {suc n} {x} ne with FLcmp x fmax
-... | tri< a ¬b ¬c = a
-... | tri≈ ¬a b ¬c = ⊥-elim ( ne b)
-... | tri> ¬a ¬b c = ⊥-elim (fmax< c)
-
-FL0≤ : {n : ℕ } → FL0 {n} f≤ fmax
-FL0≤ {zero} = case1 refl
-FL0≤ {suc zero} = case1 refl
-FL0≤ {suc n} with <-fcmp zero (fromℕ< {n} a<sa)
-... | tri< a ¬b ¬c = case2 (f<n a)
-... | tri≈ ¬a b ¬c with FL0≤ {n}
-... | case1 x = case1 (subst₂ (λ j k → (zero :: FL0) ≡ (j :: k ) ) b x refl )
-... | case2 x = case2 (subst (λ k →  (zero :: FL0) f< (k :: fmax)) b (f<t x)  )
-
-open import Relation.Binary as B hiding (Decidable; _⇔_)
-open import Data.Sum.Base as Sum --  inj₁
-open import Relation.Nary using (⌊_⌋)
-open import Data.List.Fresh
-
-FList : {n : ℕ } → Set
-FList {n} = List# (FL n) ⌊ _f<?_ ⌋
-
-fr1 : FList
-fr1 =
-   ((# 0) :: ((# 0) :: ((# 0 ) :: f0))) ∷# 
-   ((# 0) :: ((# 1) :: ((# 0 ) :: f0))) ∷# 
-   ((# 1) :: ((# 0) :: ((# 0 ) :: f0))) ∷# 
-   ((# 2) :: ((# 0) :: ((# 0 ) :: f0))) ∷# 
-   ((# 2) :: ((# 1) :: ((# 0 ) :: f0))) ∷# 
-   []
-
-open import Data.Product
-open import Relation.Nullary.Decidable hiding (⌊_⌋)
-open import Data.Bool -- hiding (T)
-open import Data.Unit.Base using (⊤ ; tt)
-
---  fresh a []        = ⊤
---  fresh a (x ∷# xs) = R a x × fresh a xs
-
--- toWitness
--- ttf< :  {n : ℕ } → {x a : FL n } → x f< a  → T (isYes (x f<? a))
--- ttf< {n} {x} {a} x<a with x f<? a
--- ... | yes y = subst (λ k → Data.Bool.T k ) refl tt
--- ... | no nn = ⊥-elim ( nn x<a )
-
-ttf : {n : ℕ } {x a : FL (suc n)} → x f< a → (y : FList {suc n}) →  fresh (FL (suc n)) ⌊ _f<?_ ⌋  a y  → fresh (FL (suc n)) ⌊ _f<?_ ⌋  x y
-ttf _ [] fr = Level.lift tt
-ttf {_} {x} {a} lt (cons a₁ y x1) (lift lt1 , x2 ) = (Level.lift (fromWitness (ttf1 lt1 lt ))) , ttf (ttf1 lt1 lt) y x1 where 
-       ttf1 : True (a f<? a₁) → x f< a  → x f< a₁
-       ttf1 t x<a = f<-trans x<a (toWitness t)
-
-FLinsert : {n : ℕ } → FL n → FList {n}  → FList {n} 
-FLfresh : {n : ℕ } → (a x : FL (suc n) ) → (y : FList {suc n} ) → a f< x
-     → fresh (FL (suc n)) ⌊ _f<?_ ⌋ a y → fresh (FL (suc n)) ⌊ _f<?_ ⌋ a (FLinsert x y)
-FLinsert {zero} f0 y = f0 ∷# []
-FLinsert {suc n} x [] = x ∷# []
-FLinsert {suc n} x (cons a y x₁) with FLcmp x a
-... | tri≈ ¬a b ¬c  = cons a y x₁
-... | tri< lt ¬b ¬c  = cons x ( cons a y x₁) ( Level.lift (fromWitness lt ) , ttf lt y  x₁) 
-FLinsert {suc n} x (cons a [] x₁) | tri> ¬a ¬b lt with FLinsert x [] | inspect ( FLinsert x ) []
-... | [] | ()
-... | cons a₁ t x₂ | e = cons a ( x  ∷# []  ) ( Level.lift (fromWitness lt) , Level.lift tt )
-FLinsert {suc n} x (cons a y yr) |  tri> ¬a ¬b a<x =
-        cons a (FLinsert x y) (FLfresh a x y a<x yr )
-
-FLfresh a x [] a<x (Level.lift tt) = Level.lift (fromWitness a<x) , Level.lift tt
-FLfresh a x (cons b [] (Level.lift tt)) a<x (Level.lift a<b , a<y) with FLcmp x b
-... | tri< x<b ¬b ¬c = Level.lift (fromWitness a<x)  , Level.lift a<b , Level.lift tt
-... | tri≈ ¬a refl ¬c = Level.lift (fromWitness a<x) , Level.lift tt
-... | tri> ¬a ¬b b<x = Level.lift a<b  ,  Level.lift (fromWitness  (f<-trans (toWitness a<b) b<x))  , Level.lift tt
-FLfresh a x (cons b y br) a<x (Level.lift a<b , a<y) with FLcmp x b
-... | tri< x<b ¬b ¬c = Level.lift (fromWitness a<x) , Level.lift a<b , ttf (toWitness a<b) y br
-... | tri≈ ¬a refl ¬c =  Level.lift (fromWitness a<x)  , ttf a<x y br
-FLfresh a x (cons b [] br) a<x (Level.lift a<b , a<y) | tri> ¬a ¬b b<x =
-    Level.lift a<b ,  Level.lift (fromWitness (f<-trans (toWitness a<b) b<x)) , Level.lift tt
-FLfresh a x (cons b (cons a₁ y x₁) br) a<x (Level.lift a<b , a<y) | tri> ¬a ¬b b<x =
-    Level.lift a<b , FLfresh a x  (cons a₁ y x₁) a<x a<y
-
-fr6 = FLinsert ((# 1) :: ((# 1) :: ((# 0 ) :: f0))) fr1 
diff -r 5e5e6cd7da2e -r c00eac825964 FLutil.agda
--- a/FLutil.agda	Sun Sep 13 09:33:57 2020 +0900
+++ b/FLutil.agda	Sun Sep 13 09:48:33 2020 +0900
@@ -1,32 +1,74 @@
-{-# OPTIONS --allow-unsolved-metas #-} 
 module FLutil where
 
 open import Level hiding ( suc ; zero )
-open import Algebra
-open import Algebra.Structures
 open import Data.Fin hiding ( _<_  ; _≤_ ; _-_ ; _+_ ; _≟_)
 open import Data.Fin.Properties hiding ( <-trans ; ≤-trans ; ≤-irrelevant ; _≟_ ) renaming ( <-cmp to <-fcmp )
 open import Data.Fin.Permutation
-open import Function hiding (id ; flip)
-open import Function.Inverse as Inverse using (_↔_; Inverse; _InverseOf_)
-open import Function.LeftInverse  using ( _LeftInverseOf_ )
-open import Function.Equality using (Π)
 open import Data.Nat -- using (ℕ; suc; zero; s≤s ; z≤n )
-open import Data.Nat.Properties -- using (<-trans)
 open import Relation.Binary.PropositionalEquality 
--- open import Data.List using (List; []; _∷_ ; length ; _++_ ; head ; tail ) renaming (reverse to rev )
-open import nat
-
-open import Symmetric
-
+open import Data.List using (List; []; _∷_ ; length ; _++_ ; head ; tail ) renaming (reverse to rev )
+open import Data.Product
 open import Relation.Nullary
 open import Data.Empty
 open import  Relation.Binary.Core
 open import  Relation.Binary.Definitions
-open import fin
-open import Putil
-open import Gutil
-open import Solvable
+open import logic
+open import nat
+
+infixr  100 _::_
+
+data  FL : (n : ℕ )→ Set where
+   f0 :  FL 0 
+   _::_ :  { n : ℕ } → Fin (suc n ) → FL n → FL (suc n)
+
+data _f<_  : {n : ℕ } (x : FL n ) (y : FL n)  → Set  where
+   f<n : {m : ℕ } {xn yn : Fin (suc m) } {xt yt : FL m} → xn Data.Fin.< yn →   (xn :: xt) f< ( yn :: yt )
+   f<t : {m : ℕ } {xn : Fin (suc m) } {xt yt : FL m} → xt f< yt →   (xn :: xt) f< ( xn :: yt )
+
+FLeq : {n : ℕ } {xn yn : Fin (suc n)} {x : FL n } {y : FL n}  → xn :: x ≡ yn :: y → ( xn ≡ yn )  × (x ≡ y )
+FLeq refl = refl , refl 
+
+f-<> :  {n : ℕ } {x : FL n } {y : FL n}  → x f< y → y f< x → ⊥
+f-<> (f<n x) (f<n x₁) = nat-<> x x₁
+f-<> (f<n x) (f<t lt2) = nat-≡< refl x
+f-<> (f<t lt) (f<n x) = nat-≡< refl x
+f-<> (f<t lt) (f<t lt2) = f-<> lt lt2
+
+f-≡< :  {n : ℕ } {x : FL n } {y : FL n}  → x ≡ y → y f< x → ⊥
+f-≡< refl (f<n x) = nat-≡< refl x
+f-≡< refl (f<t lt) = f-≡< refl lt 
+
+FLcmp : {n : ℕ } → Trichotomous {Level.zero} {FL n}  _≡_  _f<_
+FLcmp f0 f0 = tri≈ (λ ()) refl (λ ())
+FLcmp (xn :: xt) (yn :: yt) with <-fcmp xn yn
+... | tri< a ¬b ¬c = tri< (f<n a) (λ eq → nat-≡< (cong toℕ (proj₁ (FLeq eq)) ) a) (λ lt  → f-<> lt (f<n a) )
+... | tri> ¬a ¬b c = tri> (λ lt  → f-<> lt (f<n c) ) (λ eq → nat-≡< (cong toℕ (sym (proj₁ (FLeq eq)) )) c) (f<n c)
+... | tri≈ ¬a refl ¬c with FLcmp xt yt
+... | tri< a ¬b ¬c₁ = tri< (f<t a) (λ eq → ¬b (proj₂ (FLeq eq) )) (λ lt  → f-<> lt (f<t a) )
+... | tri≈ ¬a₁ refl ¬c₁ = tri≈ (λ lt → f-≡< refl lt )  refl (λ lt → f-≡< refl lt )
+... | tri> ¬a₁ ¬b c = tri> (λ lt  → f-<> lt (f<t c) ) (λ eq → ¬b (proj₂ (FLeq eq) )) (f<t c)
+
+f<-trans : {n : ℕ } { x y z : FL n } → x f< y → y f< z → x f< z
+f<-trans {suc n} (f<n x) (f<n x₁) = f<n ( Data.Fin.Properties.<-trans x x₁ )
+f<-trans {suc n} (f<n x) (f<t y<z) = f<n x
+f<-trans {suc n} (f<t x<y) (f<n x) = f<n x
+f<-trans {suc n} (f<t x<y) (f<t y<z) = f<t (f<-trans x<y y<z)
+
+infixr 250 _f<?_
+
+_f<?_ : {n  : ℕ} → (x y : FL n ) → Dec (x f< y )
+x f<? y with FLcmp x y
+... | tri< a ¬b ¬c = yes a
+... | tri≈ ¬a refl ¬c = no ( ¬a )
+... | tri> ¬a ¬b c = no ( ¬a )
+
+_f≤_ : {n : ℕ } (x : FL n ) (y : FL n)  → Set
+_f≤_ x y = (x ≡ y ) ∨  (x f< y )
+
+FL0 : {n : ℕ } → FL n
+FL0 {zero} = f0
+FL0 {suc n} = zero :: FL0
+
 
 fmax : { n : ℕ } →  FL n
 fmax {zero} = f0
@@ -47,12 +89,6 @@
 ... | tri≈ ¬a b ¬c = ⊥-elim ( ne b)
 ... | tri> ¬a ¬b c = ⊥-elim (fmax< c)
 
-FL0 : {n : ℕ } → FL n
-FL0 {zero} = f0
-FL0 {suc n} = zero :: FL0
-
-open import logic
-
 FL0≤ : {n : ℕ } → FL0 {n} f≤ fmax
 FL0≤ {zero} = case1 refl
 FL0≤ {suc zero} = case1 refl
@@ -62,20 +98,19 @@
 ... | case1 x = case1 (subst₂ (λ j k → (zero :: FL0) ≡ (j :: k ) ) b x refl )
 ... | case2 x = case2 (subst (λ k →  (zero :: FL0) f< (k :: fmax)) b (f<t x)  )
 
+open import Data.Nat.Properties using ( ≤-trans ; <-trans )
 fsuc : { n : ℕ } → (x : FL n ) → x f< fmax → FL n 
 fsuc {n} (x :: y) (f<n lt) = fromℕ< fsuc1 :: y where
     fsuc2 : toℕ x < toℕ (fromℕ< a<sa) 
     fsuc2 = lt
     fsuc1 : suc (toℕ x) < n
-    fsuc1 =  ≤-trans (s≤s lt) ( s≤s ( toℕ≤pred[n] (fromℕ< a<sa)) )
+    fsuc1 =  Data.Nat.Properties.≤-trans (s≤s lt) ( s≤s ( toℕ≤pred[n] (fromℕ< a<sa)) )
 fsuc (x :: y) (f<t lt) = x :: fsuc y lt
 
-open import Data.List
-
 flist1 :  {n : ℕ } (i : ℕ) → i < suc n → List (FL n) → List (FL n) → List (FL (suc n)) 
 flist1 zero i<n [] _ = []
 flist1 zero i<n (a ∷ x ) z  = ( zero :: a ) ∷ flist1 zero i<n x z 
-flist1 (suc i) (s≤s i<n) [] z  = flist1 i (<-trans i<n a<sa) z z 
+flist1 (suc i) (s≤s i<n) [] z  = flist1 i (Data.Nat.Properties.<-trans i<n a<sa) z z 
 flist1 (suc i) i<n (a ∷ x ) z  = ((fromℕ< i<n ) :: a ) ∷ flist1 (suc i) i<n x z 
 
 flist : {n : ℕ } → FL n → List (FL n) 
@@ -88,14 +123,14 @@
 fr4 : List (FL 4)
 fr4 = Data.List.reverse (flist (fmax {4}) )
 
-fr5 : List (List ℕ)
-fr5 = map plist (map FL→perm  (Data.List.reverse (flist (fmax {4}) )))
+-- fr5 : List (List ℕ)
+-- fr5 = map plist (map FL→perm  (Data.List.reverse (flist (fmax {4}) )))
+
 
-open import Relation.Nary using (⌊_⌋; fromWitness)
+open import Relation.Binary as B hiding (Decidable; _⇔_)
+open import Data.Sum.Base as Sum --  inj₁
+open import Relation.Nary using (⌊_⌋)
 open import Data.List.Fresh
-open import Data.List.Fresh.Relation.Unary.All
-open import Data.List.Fresh.Relation.Unary.Any as Any using (Any; here; there)
-
 
 FList : {n : ℕ } → Set
 FList {n} = List# (FL n) ⌊ _f<?_ ⌋
@@ -110,21 +145,53 @@
    []
 
 open import Data.Product
-open import Data.Maybe
+open import Relation.Nullary.Decidable hiding (⌊_⌋)
+open import Data.Bool -- hiding (T)
+open import Data.Unit.Base using (⊤ ; tt)
+
+--  fresh a []        = ⊤
+--  fresh a (x ∷# xs) = R a x × fresh a xs
+
+-- toWitness
+-- ttf< :  {n : ℕ } → {x a : FL n } → x f< a  → T (isYes (x f<? a))
+-- ttf< {n} {x} {a} x<a with x f<? a
+-- ... | yes y = subst (λ k → Data.Bool.T k ) refl tt
+-- ... | no nn = ⊥-elim ( nn x<a )
+
+ttf : {n : ℕ } {x a : FL (suc n)} → x f< a → (y : FList {suc n}) →  fresh (FL (suc n)) ⌊ _f<?_ ⌋  a y  → fresh (FL (suc n)) ⌊ _f<?_ ⌋  x y
+ttf _ [] fr = Level.lift tt
+ttf {_} {x} {a} lt (cons a₁ y x1) (lift lt1 , x2 ) = (Level.lift (fromWitness (ttf1 lt1 lt ))) , ttf (ttf1 lt1 lt) y x1 where 
+       ttf1 : True (a f<? a₁) → x f< a  → x f< a₁
+       ttf1 t x<a = f<-trans x<a (toWitness t)
+
+-- by https://gist.github.com/aristidb/1684202
 
-FLcons : {n : ℕ } → FL n → FList {n}  → FList {n} 
-FLcons {zero} f0 y = f0 ∷# []
-FLcons {suc n} x [] = x ∷# []
-FLcons {suc n} x (cons a y x₁) with FLcmp x a
-... | tri≈ ¬a b ¬c = (cons a y x₁)
-... | tri< a₁ ¬b ¬c = cons x ( cons a y x₁) (FLcons1  x₁) where
-   FLcons1 :  a # y →  x # (cons a y x₁)
-   FLcons1 ay = ? , ?
-... | tri> ¬a ¬b c with FLcons x y
-... | [] = a ∷# []
-... | cons a₁ t x₂ = cons a ( cons a₁ t x₂ ) FLcons2 where
-   FLcons2 :  fresh (FL (suc n)) ⌊ _f<?_ ⌋ a  (cons a₁ t x₂)
-   FLcons2 =  {!!} , {!!}
+FLinsert : {n : ℕ } → FL n → FList {n}  → FList {n} 
+FLfresh : {n : ℕ } → (a x : FL (suc n) ) → (y : FList {suc n} ) → a f< x
+     → fresh (FL (suc n)) ⌊ _f<?_ ⌋ a y → fresh (FL (suc n)) ⌊ _f<?_ ⌋ a (FLinsert x y)
+FLinsert {zero} f0 y = f0 ∷# []
+FLinsert {suc n} x [] = x ∷# []
+FLinsert {suc n} x (cons a y x₁) with FLcmp x a
+... | tri≈ ¬a b ¬c  = cons a y x₁
+... | tri< lt ¬b ¬c  = cons x ( cons a y x₁) ( Level.lift (fromWitness lt ) , ttf lt y  x₁) 
+FLinsert {suc n} x (cons a [] x₁) | tri> ¬a ¬b lt with FLinsert x [] | inspect ( FLinsert x ) []
+... | [] | ()
+... | cons a₁ t x₂ | e = cons a ( x  ∷# []  ) ( Level.lift (fromWitness lt) , Level.lift tt )
+FLinsert {suc n} x (cons a y yr) |  tri> ¬a ¬b a<x =
+        cons a (FLinsert x y) (FLfresh a x y a<x yr )
 
-fr6 = FLcons ((# 1) :: ((# 1) :: ((# 0 ) :: f0))) fr1 
+FLfresh a x [] a<x (Level.lift tt) = Level.lift (fromWitness a<x) , Level.lift tt
+FLfresh a x (cons b [] (Level.lift tt)) a<x (Level.lift a<b , a<y) with FLcmp x b
+... | tri< x<b ¬b ¬c  = Level.lift (fromWitness a<x) , Level.lift a<b , Level.lift tt
+... | tri≈ ¬a refl ¬c = Level.lift (fromWitness a<x) , Level.lift tt
+... | tri> ¬a ¬b b<x =  Level.lift a<b  ,  Level.lift (fromWitness  (f<-trans (toWitness a<b) b<x))  , Level.lift tt
+FLfresh a x (cons b y br) a<x (Level.lift a<b , a<y) with FLcmp x b
+... | tri< x<b ¬b ¬c =  Level.lift (fromWitness a<x) , Level.lift a<b , ttf (toWitness a<b) y br
+... | tri≈ ¬a refl ¬c = Level.lift (fromWitness a<x) , ttf a<x y br
+FLfresh a x (cons b [] br) a<x (Level.lift a<b , a<y) | tri> ¬a ¬b b<x =
+    Level.lift a<b , Level.lift (fromWitness (f<-trans (toWitness a<b) b<x)) , Level.lift tt
+FLfresh a x (cons b (cons a₁ y x₁) br) a<x (Level.lift a<b , a<y) | tri> ¬a ¬b b<x =
+    Level.lift a<b , FLfresh a x (cons a₁ y x₁) a<x a<y
 
+fr6 = FLinsert ((# 1) :: ((# 1) :: ((# 0 ) :: f0))) fr1 
+