670 lines
21 KiB
Coq
670 lines
21 KiB
Coq
Require Import Autosubst2.core Autosubst2.fintype Autosubst2.syntax.
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Require Import fp_red.
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From Hammer Require Import Tactics.
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From Equations Require Import Equations.
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Require Import ssreflect ssrbool.
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Require Import Logic.PropExtensionality (propositional_extensionality).
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From stdpp Require Import relations (rtc(..), rtc_subrel).
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Import Psatz.
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Definition ProdSpace (PA : Tm 0 -> Prop)
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(PF : Tm 0 -> (Tm 0 -> Prop) -> Prop) b : Prop :=
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forall a PB, PA a -> PF a PB -> PB (App b a).
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Definition SumSpace (PA : Tm 0 -> Prop)
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(PF : Tm 0 -> (Tm 0 -> Prop) -> Prop) t : Prop :=
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exists a b, rtc RPar.R t (Pair a b) /\ PA a /\ (forall PB, PF a PB -> PB b).
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Definition BindSpace p := if p is TPi then ProdSpace else SumSpace.
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Reserved Notation "⟦ A ⟧ i ;; I ↘ S" (at level 70).
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Inductive InterpExt i (I : nat -> Tm 0 -> Prop) : Tm 0 -> (Tm 0 -> Prop) -> Prop :=
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| InterpExt_Bind p A B PA PF :
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⟦ A ⟧ i ;; I ↘ PA ->
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(forall a, PA a -> exists PB, PF a PB) ->
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(forall a PB, PF a PB -> ⟦ subst_Tm (scons a VarTm) B ⟧ i ;; I ↘ PB) ->
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⟦ TBind p A B ⟧ i ;; I ↘ BindSpace p PA PF
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| InterpExt_Univ j :
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j < i ->
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⟦ Univ j ⟧ i ;; I ↘ (I j)
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| InterpExt_Step A A0 PA :
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RPar.R A A0 ->
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⟦ A0 ⟧ i ;; I ↘ PA ->
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⟦ A ⟧ i ;; I ↘ PA
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where "⟦ A ⟧ i ;; I ↘ S" := (InterpExt i I A S).
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Lemma InterpExt_Univ' i I j (PF : Tm 0 -> Prop) :
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PF = I j ->
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j < i ->
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⟦ Univ j ⟧ i ;; I ↘ PF.
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Proof. hauto lq:on ctrs:InterpExt. Qed.
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Infix "<?" := Compare_dec.lt_dec (at level 60).
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Equations InterpUnivN (i : nat) : Tm 0 -> (Tm 0 -> Prop) -> Prop by wf i lt :=
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InterpUnivN i := @InterpExt i
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(fun j A =>
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match j <? i with
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| left _ => exists PA, InterpUnivN j A PA
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| right _ => False
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end).
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Arguments InterpUnivN .
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Lemma InterpExt_lt_impl i I I' A (PA : Tm 0 -> Prop) :
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(forall j, j < i -> I j = I' j) ->
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⟦ A ⟧ i ;; I ↘ PA ->
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⟦ A ⟧ i ;; I' ↘ PA.
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Proof.
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move => hI h.
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elim : A PA /h.
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- hauto lq:on rew:off ctrs:InterpExt.
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- hauto q:on ctrs:InterpExt.
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- hauto lq:on ctrs:InterpExt.
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Qed.
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Lemma InterpExt_lt_eq i I I' A (PA : Tm 0 -> Prop) :
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(forall j, j < i -> I j = I' j) ->
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⟦ A ⟧ i ;; I ↘ PA =
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⟦ A ⟧ i ;; I' ↘ PA.
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Proof.
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move => hI. apply propositional_extensionality.
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have : forall j, j < i -> I' j = I j by sfirstorder.
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firstorder using InterpExt_lt_impl.
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Qed.
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Notation "⟦ A ⟧ i ↘ S" := (InterpUnivN i A S) (at level 70).
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Lemma InterpUnivN_nolt i :
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InterpUnivN i = InterpExt i (fun j (A : Tm 0) => exists PA, ⟦ A ⟧ j ↘ PA).
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Proof.
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simp InterpUnivN.
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extensionality A. extensionality PA.
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set I0 := (fun _ => _).
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set I1 := (fun _ => _).
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apply InterpExt_lt_eq.
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hauto q:on.
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Qed.
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#[export]Hint Rewrite @InterpUnivN_nolt : InterpUniv.
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Lemma RPar_substone n (a b : Tm (S n)) (c : Tm n):
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RPar.R a b -> RPar.R (subst_Tm (scons c VarTm) a) (subst_Tm (scons c VarTm) b).
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Proof. hauto l:on inv:option use:RPar.substing, RPar.refl. Qed.
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Lemma InterpExt_Bind_inv p i I (A : Tm 0) B P
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(h : ⟦ TBind p A B ⟧ i ;; I ↘ P) :
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exists (PA : Tm 0 -> Prop) (PF : Tm 0 -> (Tm 0 -> Prop) -> Prop),
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⟦ A ⟧ i ;; I ↘ PA /\
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(forall a, PA a -> exists PB, PF a PB) /\
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(forall a PB, PF a PB -> ⟦ subst_Tm (scons a VarTm) B ⟧ i ;; I ↘ PB) /\
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P = BindSpace p PA PF.
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Proof.
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move E : (TBind p A B) h => T h.
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move : A B E.
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elim : T P / h => //.
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- hauto l:on.
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- move => A A0 PA hA hA0 hPi A1 B ?. subst.
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elim /RPar.inv : hA => //= _ p0 A2 A3 B0 B1 hA1 hB0 [*]. subst.
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hauto lq:on ctrs:InterpExt use:RPar_substone.
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Qed.
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Lemma InterpExt_Univ_inv i I j P
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(h : ⟦ Univ j ⟧ i ;; I ↘ P) :
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P = I j /\ j < i.
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Proof.
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move : h.
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move E : (Univ j) => T h. move : j E.
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elim : T P /h => //.
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- hauto l:on.
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- hauto lq:on rew:off inv:RPar.R.
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Qed.
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Lemma InterpExt_Bind_nopf p i I (A : Tm 0) B PA :
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⟦ A ⟧ i ;; I ↘ PA ->
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(forall a, PA a -> exists PB, ⟦ subst_Tm (scons a VarTm) B ⟧ i ;; I ↘ PB) ->
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⟦ TBind p A B ⟧ i ;; I ↘ (BindSpace p PA (fun a PB => ⟦ subst_Tm (scons a VarTm) B ⟧ i ;; I ↘ PB)).
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Proof.
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move => h0 h1. apply InterpExt_Bind =>//.
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Qed.
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Lemma InterpUnivN_Fun_nopf p i (A : Tm 0) B PA :
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⟦ A ⟧ i ↘ PA ->
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(forall a, PA a -> exists PB, ⟦ subst_Tm (scons a VarTm) B ⟧ i ↘ PB) ->
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⟦ TBind p A B ⟧ i ↘ (BindSpace p PA (fun a PB => ⟦ subst_Tm (scons a VarTm) B ⟧ i ↘ PB)).
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Proof.
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hauto l:on use:InterpExt_Bind_nopf rew:db:InterpUniv.
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Qed.
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Lemma InterpExt_cumulative i j I (A : Tm 0) PA :
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i <= j ->
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⟦ A ⟧ i ;; I ↘ PA ->
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⟦ A ⟧ j ;; I ↘ PA.
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Proof.
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move => h h0.
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elim : A PA /h0;
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hauto l:on ctrs:InterpExt solve+:(by lia).
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Qed.
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Lemma InterpUnivN_cumulative i (A : Tm 0) PA :
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⟦ A ⟧ i ↘ PA -> forall j, i <= j ->
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⟦ A ⟧ j ↘ PA.
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Proof.
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hauto l:on rew:db:InterpUniv use:InterpExt_cumulative.
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Qed.
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Lemma InterpExt_preservation i I (A : Tm 0) B P (h : InterpExt i I A P) :
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RPar.R A B ->
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⟦ B ⟧ i ;; I ↘ P.
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Proof.
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move : B.
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elim : A P / h; auto.
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- move => p A B PA PF hPA ihPA hPB hPB' ihPB T hT.
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elim /RPar.inv : hT => //.
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move => hPar p0 A0 A1 B0 B1 h0 h1 [? ?] ? ?; subst.
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apply InterpExt_Bind; auto => a PB hPB0.
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apply : ihPB; eauto.
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sfirstorder use:RPar.cong, RPar.refl.
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- hauto lq:on inv:RPar.R ctrs:InterpExt.
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- move => A B P h0 h1 ih1 C hC.
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have [D [h2 h3]] := RPar_diamond _ _ _ _ h0 hC.
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hauto lq:on ctrs:InterpExt.
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Qed.
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Lemma InterpUnivN_preservation i (A : Tm 0) B P (h : ⟦ A ⟧ i ↘ P) :
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RPar.R A B ->
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⟦ B ⟧ i ↘ P.
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Proof. hauto l:on rew:db:InterpUnivN use: InterpExt_preservation. Qed.
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Lemma InterpExt_back_preservation_star i I (A : Tm 0) B P (h : ⟦ B ⟧ i ;; I ↘ P) :
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rtc RPar.R A B ->
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⟦ A ⟧ i ;; I ↘ P.
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Proof. induction 1; hauto l:on ctrs:InterpExt. Qed.
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Lemma InterpExt_preservation_star i I (A : Tm 0) B P (h : ⟦ A ⟧ i ;; I ↘ P) :
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rtc RPar.R A B ->
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⟦ B ⟧ i ;; I ↘ P.
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Proof. induction 1; hauto l:on use:InterpExt_preservation. Qed.
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Lemma InterpUnivN_preservation_star i (A : Tm 0) B P (h : ⟦ A ⟧ i ↘ P) :
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rtc RPar.R A B ->
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⟦ B ⟧ i ↘ P.
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Proof. hauto l:on rew:db:InterpUnivN use:InterpExt_preservation_star. Qed.
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Lemma InterpUnivN_back_preservation_star i (A : Tm 0) B P (h : ⟦ B ⟧ i ↘ P) :
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rtc RPar.R A B ->
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⟦ A ⟧ i ↘ P.
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Proof. hauto l:on rew:db:InterpUnivN use:InterpExt_back_preservation_star. Qed.
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Lemma InterpExtInv i I (A : Tm 0) PA :
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⟦ A ⟧ i ;; I ↘ PA ->
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exists B, hfb B /\ rtc RPar.R A B /\ ⟦ B ⟧ i ;; I ↘ PA.
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Proof.
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move => h. elim : A PA /h.
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- move => p A B PA PF hPA _ hPF hPF0 _.
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exists (TBind p A B). repeat split => //=.
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apply rtc_refl.
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hauto l:on ctrs:InterpExt.
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- move => j ?. exists (Univ j).
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hauto l:on ctrs:InterpExt.
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- hauto lq:on ctrs:rtc.
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Qed.
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Lemma RPars_Pars (A B : Tm 0) :
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rtc RPar.R A B ->
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rtc Par.R A B.
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Proof. hauto lq:on use:RPar_Par, rtc_subrel. Qed.
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Lemma RPars_join (A B : Tm 0) :
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rtc RPar.R A B -> join A B.
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Proof. hauto lq:on ctrs:rtc use:RPars_Pars. Qed.
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Lemma bindspace_iff p (PA : Tm 0 -> Prop) PF PF0 b :
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(forall (a : Tm 0) (PB PB0 : Tm 0 -> Prop), PF a PB -> PF0 a PB0 -> PB = PB0) ->
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(forall a, PA a -> exists PB, PF a PB) ->
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(forall a, PA a -> exists PB0, PF0 a PB0) ->
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(BindSpace p PA PF b <-> BindSpace p PA PF0 b).
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Proof.
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rewrite /BindSpace => h hPF hPF0.
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case : p => /=.
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- rewrite /ProdSpace.
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split.
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move => h1 a PB ha hPF'.
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specialize hPF with (1 := ha).
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specialize hPF0 with (1 := ha).
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sblast.
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move => ? a PB ha.
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specialize hPF with (1 := ha).
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specialize hPF0 with (1 := ha).
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sblast.
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- rewrite /SumSpace.
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hauto lq:on rew:off.
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Qed.
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Lemma InterpExt_Join i I (A B : Tm 0) PA PB :
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⟦ A ⟧ i ;; I ↘ PA ->
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⟦ B ⟧ i ;; I ↘ PB ->
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join A B ->
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PA = PB.
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Proof.
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move => h. move : B PB. elim : A PA /h.
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- move => p A B PA PF hPA ihPA hTot hRes ihPF U PU /InterpExtInv.
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move => [B0 []].
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case : B0 => //=.
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+ move => p0 A0 B0 _ [hr hPi].
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move /InterpExt_Bind_inv : hPi.
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move => [PA0][PF0][hPA0][hTot0][hRes0]?. subst.
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move => hjoin.
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have{}hr : join U (TBind p0 A0 B0) by auto using RPars_join.
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have hj : join (TBind p A B) (TBind p0 A0 B0) by eauto using join_transitive.
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have {hj} : p0 = p /\ join A A0 /\ join B B0 by hauto l:on use:join_pi_inj.
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move => [? [h0 h1]]. subst.
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have ? : PA0 = PA by hauto l:on. subst.
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rewrite /ProdSpace.
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extensionality b.
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apply propositional_extensionality.
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apply bindspace_iff; eauto.
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move => a PB PB0 hPB hPB0.
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apply : ihPF; eauto.
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by apply join_substing.
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+ move => j _.
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move => [h0 h1] h.
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have ? : join U (Univ j) by eauto using RPars_join.
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have : join (TBind p A B) (Univ j) by eauto using join_transitive.
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move => ?. exfalso.
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eauto using join_univ_pi_contra.
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- move => j ? B PB /InterpExtInv.
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move => [+ []]. case => //=.
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+ move => p A0 B0 _ [].
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move /RPars_join => *.
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have ? : join (TBind p A0 B0) (Univ j) by eauto using join_symmetric, join_transitive.
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exfalso.
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eauto using join_univ_pi_contra.
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+ move => m _ [/RPars_join h0 + h1].
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have /join_univ_inj {h0 h1} ? : join (Univ j : Tm 0) (Univ m) by eauto using join_transitive.
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subst.
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move /InterpExt_Univ_inv. firstorder.
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- move => A A0 PA h.
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have /join_symmetric {}h : join A A0 by hauto lq:on ctrs:rtc use:RPar_Par, relations.rtc_once.
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eauto using join_transitive.
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Qed.
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Lemma InterpUniv_Join i (A B : Tm 0) PA PB :
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⟦ A ⟧ i ↘ PA ->
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⟦ B ⟧ i ↘ PB ->
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join A B ->
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PA = PB.
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Proof. hauto l:on use:InterpExt_Join rew:db:InterpUniv. Qed.
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Lemma InterpUniv_Bind_inv p i (A : Tm 0) B P
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(h : ⟦ TBind p A B ⟧ i ↘ P) :
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exists (PA : Tm 0 -> Prop) (PF : Tm 0 -> (Tm 0 -> Prop) -> Prop),
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⟦ A ⟧ i ↘ PA /\
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(forall a, PA a -> exists PB, PF a PB) /\
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(forall a PB, PF a PB -> ⟦ subst_Tm (scons a VarTm) B ⟧ i ↘ PB) /\
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P = BindSpace p PA PF.
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Proof. hauto l:on use:InterpExt_Bind_inv rew:db:InterpUniv. Qed.
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Lemma InterpUniv_Univ_inv i j P
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(h : ⟦ Univ j ⟧ i ↘ P) :
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P = (fun (A : Tm 0) => exists PA, ⟦ A ⟧ j ↘ PA) /\ j < i.
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Proof. hauto l:on use:InterpExt_Univ_inv rew:db:InterpUniv. Qed.
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Lemma InterpExt_Functional i I (A B : Tm 0) PA PB :
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⟦ A ⟧ i ;; I ↘ PA ->
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⟦ A ⟧ i ;; I ↘ PB ->
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PA = PB.
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Proof. hauto use:InterpExt_Join, join_refl. Qed.
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Lemma InterpUniv_Functional i (A : Tm 0) PA PB :
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⟦ A ⟧ i ↘ PA ->
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⟦ A ⟧ i ↘ PB ->
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PA = PB.
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Proof. hauto use:InterpExt_Functional rew:db:InterpUniv. Qed.
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Lemma InterpUniv_Join' i j (A B : Tm 0) PA PB :
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⟦ A ⟧ i ↘ PA ->
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⟦ B ⟧ j ↘ PB ->
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join A B ->
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PA = PB.
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Proof.
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have [? ?] : i <= max i j /\ j <= max i j by lia.
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move => hPA hPB.
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have : ⟦ A ⟧ (max i j) ↘ PA by eauto using InterpUnivN_cumulative.
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have : ⟦ B ⟧ (max i j) ↘ PB by eauto using InterpUnivN_cumulative.
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eauto using InterpUniv_Join.
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Qed.
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Lemma InterpUniv_Functional' i j A PA PB :
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⟦ A ⟧ i ↘ PA ->
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⟦ A ⟧ j ↘ PB ->
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PA = PB.
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Proof.
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hauto l:on use:InterpUniv_Join', join_refl.
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Qed.
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Lemma InterpExt_Bind_inv_nopf i I p A B P (h : ⟦TBind p A B ⟧ i ;; I ↘ P) :
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exists (PA : Tm 0 -> Prop),
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⟦ A ⟧ i ;; I ↘ PA /\
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(forall a, PA a -> exists PB, ⟦ subst_Tm (scons a VarTm) B ⟧ i ;; I ↘ PB) /\
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P = BindSpace p PA (fun a PB => ⟦ subst_Tm (scons a VarTm) B ⟧ i ;; I ↘ PB).
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Proof.
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move /InterpExt_Bind_inv : h. intros (PA & PF & hPA & hPF & hPF' & ?); subst.
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exists PA. repeat split => //.
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- sfirstorder.
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- extensionality b.
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case : p => /=.
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+ extensionality a.
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extensionality PB.
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extensionality ha.
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apply propositional_extensionality.
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split.
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* hecrush use:InterpExt_Functional.
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* sfirstorder.
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+ rewrite /SumSpace. apply propositional_extensionality.
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split; hauto q:on use:InterpExt_Functional.
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Qed.
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Lemma InterpUniv_Bind_inv_nopf i p A B P (h : ⟦TBind p A B ⟧ i ↘ P) :
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exists (PA : Tm 0 -> Prop),
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⟦ A ⟧ i ↘ PA /\
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(forall a, PA a -> exists PB, ⟦ subst_Tm (scons a VarTm) B ⟧ i ↘ PB) /\
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P = BindSpace p PA (fun a PB => ⟦ subst_Tm (scons a VarTm) B ⟧ i ↘ PB).
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Proof. hauto l:on use:InterpExt_Bind_inv_nopf rew:db:InterpUniv. Qed.
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Lemma InterpExt_back_clos i I (A : Tm 0) PA :
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(forall j, forall a b, (RPar.R a b) -> I j b -> I j a) ->
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⟦ A ⟧ i ;; I ↘ PA ->
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forall a b, (RPar.R a b) ->
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PA b -> PA a.
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Proof.
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move => hI h.
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elim : A PA /h.
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- move => p A B PA PF hPA ihPA hTot hRes ihPF a b hr.
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case : p => //=.
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+ have : forall b0 b1 a, RPar.R b0 b1 -> RPar.R (App b0 a) (App b1 a)
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by hauto lq:on ctrs:RPar.R use:RPar.refl.
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hauto lq:on rew:off unfold:ProdSpace.
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+ hauto lq:on ctrs:rtc unfold:SumSpace.
|
||
- eauto.
|
||
- eauto.
|
||
Qed.
|
||
|
||
Lemma InterpUniv_back_clos i (A : Tm 0) PA :
|
||
⟦ A ⟧ i ↘ PA ->
|
||
forall a b, (RPar.R a b) ->
|
||
PA b -> PA a.
|
||
Proof.
|
||
simp InterpUniv.
|
||
apply InterpExt_back_clos.
|
||
hauto lq:on ctrs:rtc use:InterpUnivN_back_preservation_star.
|
||
Qed.
|
||
|
||
Lemma InterpUniv_back_clos_star i (A : Tm 0) PA :
|
||
⟦ A ⟧ i ↘ PA ->
|
||
forall a b, rtc RPar.R a b ->
|
||
PA b -> PA a.
|
||
Proof.
|
||
move => h a b.
|
||
induction 1=> //.
|
||
hauto lq:on use:InterpUniv_back_clos.
|
||
Qed.
|
||
|
||
Definition ρ_ok {n} Γ (ρ : fin n -> Tm 0) := forall i m PA,
|
||
⟦ subst_Tm ρ (Γ i) ⟧ m ↘ PA -> PA (ρ i).
|
||
|
||
Definition SemWt {n} Γ (a A : Tm n) := forall ρ, ρ_ok Γ ρ -> exists m PA, ⟦ subst_Tm ρ A ⟧ m ↘ PA /\ PA (subst_Tm ρ a).
|
||
Notation "Γ ⊨ a ∈ A" := (SemWt Γ a A) (at level 70).
|
||
|
||
(* Semantic context wellformedness *)
|
||
Definition SemWff {n} Γ := forall (i : fin n), exists j, Γ ⊨ Γ i ∈ Univ j.
|
||
Notation "⊨ Γ" := (SemWff Γ) (at level 70).
|
||
|
||
Lemma ρ_ok_nil ρ :
|
||
ρ_ok null ρ.
|
||
Proof. rewrite /ρ_ok. inversion i; subst. Qed.
|
||
|
||
Lemma ρ_ok_cons n i (Γ : fin n -> Tm n) ρ a PA A :
|
||
⟦ subst_Tm ρ A ⟧ i ↘ PA -> PA a ->
|
||
ρ_ok Γ ρ ->
|
||
ρ_ok (funcomp (ren_Tm shift) (scons A Γ)) ((scons a ρ)).
|
||
Proof.
|
||
move => h0 h1 h2.
|
||
rewrite /ρ_ok.
|
||
move => j.
|
||
destruct j as [j|].
|
||
- move => m PA0. asimpl => ?.
|
||
firstorder.
|
||
- move => m PA0. asimpl => h3.
|
||
have ? : PA0 = PA by eauto using InterpUniv_Functional'.
|
||
by subst.
|
||
Qed.
|
||
|
||
Definition renaming_ok {n m} (Γ : fin n -> Tm n) (Δ : fin m -> Tm m) (ξ : fin m -> fin n) :=
|
||
forall (i : fin m), ren_Tm ξ (Δ i) = Γ (ξ i).
|
||
|
||
Lemma ρ_ok_renaming n m (Γ : fin n -> Tm n) ρ :
|
||
forall (Δ : fin m -> Tm m) ξ,
|
||
renaming_ok Γ Δ ξ ->
|
||
ρ_ok Γ ρ ->
|
||
ρ_ok Δ (funcomp ρ ξ).
|
||
Proof.
|
||
move => Δ ξ hξ hρ.
|
||
rewrite /ρ_ok => i m' PA.
|
||
rewrite /renaming_ok in hξ.
|
||
rewrite /ρ_ok in hρ.
|
||
move => h.
|
||
rewrite /funcomp.
|
||
apply hρ with (m := m').
|
||
move : h. rewrite -hξ.
|
||
by asimpl.
|
||
Qed.
|
||
|
||
Lemma renaming_SemWt {n} Γ a A :
|
||
Γ ⊨ a ∈ A ->
|
||
forall {m} Δ (ξ : fin n -> fin m),
|
||
renaming_ok Δ Γ ξ ->
|
||
Δ ⊨ ren_Tm ξ a ∈ ren_Tm ξ A.
|
||
Proof.
|
||
rewrite /SemWt => h m Δ ξ hξ ρ hρ.
|
||
have /h hρ' : (ρ_ok Γ (funcomp ρ ξ)) by eauto using ρ_ok_renaming.
|
||
hauto q:on solve+:(by asimpl).
|
||
Qed.
|
||
|
||
Lemma weakening_Sem n Γ (a : Tm n) A B i
|
||
(h0 : Γ ⊨ B ∈ Univ i)
|
||
(h1 : Γ ⊨ a ∈ A) :
|
||
funcomp (ren_Tm shift) (scons B Γ) ⊨ ren_Tm shift a ∈ ren_Tm shift A.
|
||
Proof.
|
||
apply : renaming_SemWt; eauto.
|
||
hauto lq:on inv:option unfold:renaming_ok.
|
||
Qed.
|
||
|
||
Lemma SemWt_Univ n Γ (A : Tm n) i :
|
||
Γ ⊨ A ∈ Univ i <->
|
||
forall ρ, ρ_ok Γ ρ -> exists S, ⟦ subst_Tm ρ A ⟧ i ↘ S.
|
||
Proof.
|
||
rewrite /SemWt.
|
||
split.
|
||
- hauto lq:on rew:off use:InterpUniv_Univ_inv.
|
||
- move => /[swap] ρ /[apply].
|
||
move => [PA hPA].
|
||
exists (S i). eexists.
|
||
split.
|
||
+ simp InterpUniv. apply InterpExt_Univ. lia.
|
||
+ simpl. eauto.
|
||
Qed.
|
||
|
||
(* Structural laws for Semantic context wellformedness *)
|
||
Lemma SemWff_nil : SemWff null.
|
||
Proof. case. Qed.
|
||
|
||
Lemma SemWff_cons n Γ (A : Tm n) i :
|
||
⊨ Γ ->
|
||
Γ ⊨ A ∈ Univ i ->
|
||
(* -------------- *)
|
||
⊨ funcomp (ren_Tm shift) (scons A Γ).
|
||
Proof.
|
||
move => h h0.
|
||
move => j. destruct j as [j|].
|
||
- move /(_ j) : h => [k hk].
|
||
exists k. change (Univ k) with (ren_Tm shift (Univ k : Tm n)).
|
||
eauto using weakening_Sem.
|
||
- hauto q:on use:weakening_Sem.
|
||
Qed.
|
||
|
||
(* Semantic typing rules *)
|
||
Lemma ST_Var n Γ (i : fin n) :
|
||
⊨ Γ ->
|
||
Γ ⊨ VarTm i ∈ Γ i.
|
||
Proof.
|
||
move /(_ i) => [j /SemWt_Univ h].
|
||
rewrite /SemWt => ρ /[dup] hρ {}/h [S hS].
|
||
exists j, S.
|
||
asimpl. firstorder.
|
||
Qed.
|
||
|
||
Lemma ST_Bind n Γ i j p (A : Tm n) (B : Tm (S n)) :
|
||
Γ ⊨ A ∈ Univ i ->
|
||
funcomp (ren_Tm shift) (scons A Γ) ⊨ B ∈ Univ j ->
|
||
Γ ⊨ TBind p A B ∈ Univ (max i j).
|
||
Proof.
|
||
move => /SemWt_Univ h0 /SemWt_Univ h1.
|
||
apply SemWt_Univ => ρ hρ.
|
||
move /h0 : (hρ){h0} => [S hS].
|
||
eexists => /=.
|
||
have ? : i <= Nat.max i j by lia.
|
||
apply InterpUnivN_Fun_nopf.
|
||
- eauto using InterpUnivN_cumulative.
|
||
- move => *. asimpl. hauto l:on use:InterpUnivN_cumulative, ρ_ok_cons.
|
||
Qed.
|
||
|
||
Lemma ST_Conv n Γ (a : Tm n) A B i :
|
||
Γ ⊨ a ∈ A ->
|
||
Γ ⊨ B ∈ Univ i ->
|
||
join A B ->
|
||
Γ ⊨ a ∈ B.
|
||
Proof.
|
||
move => ha /SemWt_Univ h h0.
|
||
move => ρ hρ.
|
||
have {}h0 : join (subst_Tm ρ A) (subst_Tm ρ B) by eauto using join_substing.
|
||
move /ha : (hρ){ha} => [m [PA [h1 h2]]].
|
||
move /h : (hρ){h} => [S hS].
|
||
have ? : PA = S by eauto using InterpUniv_Join'. subst.
|
||
eauto.
|
||
Qed.
|
||
|
||
Lemma ST_Abs n Γ (a : Tm (S n)) A B i :
|
||
Γ ⊨ TBind TPi A B ∈ (Univ i) ->
|
||
funcomp (ren_Tm shift) (scons A Γ) ⊨ a ∈ B ->
|
||
Γ ⊨ Abs a ∈ TBind TPi A B.
|
||
Proof.
|
||
rename a into b.
|
||
move /SemWt_Univ => + hb ρ hρ.
|
||
move /(_ _ hρ) => [PPi hPPi].
|
||
exists i, PPi. split => //.
|
||
simpl in hPPi.
|
||
move /InterpUniv_Bind_inv_nopf : hPPi.
|
||
move => [PA [hPA [hTot ?]]]. subst=>/=.
|
||
move => a PB ha. asimpl => hPB.
|
||
move : ρ_ok_cons (hPA) (hρ) (ha). repeat move/[apply].
|
||
move /hb.
|
||
intros (m & PB0 & hPB0 & hPB0').
|
||
replace PB0 with PB in * by hauto l:on use:InterpUniv_Functional'.
|
||
apply : InterpUniv_back_clos; eauto.
|
||
apply : RPar.AppAbs'; eauto using RPar.refl.
|
||
by asimpl.
|
||
Qed.
|
||
|
||
Lemma ST_App n Γ (b a : Tm n) A B :
|
||
Γ ⊨ b ∈ TBind TPi A B ->
|
||
Γ ⊨ a ∈ A ->
|
||
Γ ⊨ App b a ∈ subst_Tm (scons a VarTm) B.
|
||
Proof.
|
||
move => hf hb ρ hρ.
|
||
move /(_ ρ hρ) : hf; intros (i & PPi & hPi & hf).
|
||
move /(_ ρ hρ) : hb; intros (j & PA & hPA & hb).
|
||
simpl in hPi.
|
||
move /InterpUniv_Bind_inv_nopf : hPi. intros (PA0 & hPA0 & hTot & ?). subst.
|
||
have ? : PA0 = PA by eauto using InterpUniv_Functional'. subst.
|
||
move : hf (hb). move/[apply].
|
||
move : hTot hb. move/[apply].
|
||
asimpl. hauto lq:on.
|
||
Qed.
|
||
|
||
Lemma ST_Pair n Γ (a b : Tm n) A B i :
|
||
Γ ⊨ TBind TSig A B ∈ (Univ i) ->
|
||
Γ ⊨ a ∈ A ->
|
||
Γ ⊨ b ∈ subst_Tm (scons a VarTm) B ->
|
||
Γ ⊨ Pair a b ∈ TBind TSig A B.
|
||
Proof.
|
||
move /SemWt_Univ => + ha hb ρ hρ.
|
||
move /(_ _ hρ) => [PPi hPPi].
|
||
exists i, PPi. split => //.
|
||
simpl in hPPi.
|
||
move /InterpUniv_Bind_inv_nopf : hPPi.
|
||
move => [PA [hPA [hTot ?]]]. subst=>/=.
|
||
rewrite /SumSpace.
|
||
exists (subst_Tm ρ a), (subst_Tm ρ b).
|
||
split.
|
||
- hauto l:on use:Pars.substing.
|
||
- move /ha : (hρ){ha}.
|
||
move => [m][PA0][h0]h1.
|
||
move /hb : (hρ){hb}.
|
||
move => [k][PB][h2]h3.
|
||
have ? : PA0 = PA by eauto using InterpUniv_Functional'. subst.
|
||
split => // PB0.
|
||
move : h2. asimpl => *.
|
||
have ? : PB0 = PB by eauto using InterpUniv_Functional'. by subst.
|
||
Qed.
|
||
|
||
Lemma ST_Proj1 n Γ (a : Tm n) A B :
|
||
Γ ⊨ a ∈ TBind TSig A B ->
|
||
Γ ⊨ Proj PL a ∈ A.
|
||
Proof.
|
||
move => h ρ /[dup]hρ {}/h [m][PA][/= /InterpUniv_Bind_inv_nopf h0]h1.
|
||
move : h0 => [S][h2][h3]?. subst.
|
||
move : h1 => /=.
|
||
rewrite /SumSpace.
|
||
move => [a0 [b0 [h4 [h5 h6]]]].
|
||
exists m, S. split => //=.
|
||
have {}h4 : rtc RPar.R (Proj PL (subst_Tm ρ a)) (Proj PL (Pair a0 b0)) by eauto using RPars.ProjCong.
|
||
have ? : RPar.R (Proj PL (Pair a0 b0)) a0 by hauto l:on use:RPar.refl, RPar.ProjPair'.
|
||
have : rtc RPar.R (Proj PL (subst_Tm ρ a)) a0 by eauto using @relations.rtc_r.
|
||
move => h.
|
||
apply : InterpUniv_back_clos_star; eauto.
|
||
Qed.
|
||
|
||
Lemma substing_RPar n m (A : Tm (S n)) ρ (B : Tm m) C :
|
||
RPar.R B C ->
|
||
RPar.R (subst_Tm (scons B ρ) A) (subst_Tm (scons C ρ) A).
|
||
Proof. hauto lq:on inv:option use:RPar.morphing, RPar.refl. Qed.
|
||
|
||
Lemma substing_RPars n m (A : Tm (S n)) ρ (B : Tm m) C :
|
||
rtc RPar.R B C ->
|
||
rtc RPar.R (subst_Tm (scons B ρ) A) (subst_Tm (scons C ρ) A).
|
||
Proof. induction 1; hauto lq:on ctrs:rtc use:substing_RPar. Qed.
|
||
|
||
Lemma ST_Proj2 n Γ (a : Tm n) A B :
|
||
Γ ⊨ a ∈ TBind TSig A B ->
|
||
Γ ⊨ Proj PR a ∈ subst_Tm (scons (Proj PL a) VarTm) B.
|
||
Proof.
|
||
move => h ρ hρ.
|
||
move : (hρ) => {}/h [m][PA][/= /InterpUniv_Bind_inv_nopf h0]h1.
|
||
move : h0 => [S][h2][h3]?. subst.
|
||
move : h1 => /=.
|
||
rewrite /SumSpace.
|
||
move => [a0 [b0 [h4 [h5 h6]]]].
|
||
specialize h3 with (1 := h5).
|
||
move : h3 => [PB hPB].
|
||
have hr : forall p, rtc RPar.R (Proj p (subst_Tm ρ a)) (Proj p (Pair a0 b0)) by eauto using RPars.ProjCong.
|
||
have hrl : RPar.R (Proj PL (Pair a0 b0)) a0 by hauto l:on use:RPar.ProjPair', RPar.refl.
|
||
have hrr : RPar.R (Proj PR (Pair a0 b0)) b0 by hauto l:on use:RPar.ProjPair', RPar.refl.
|
||
exists m, PB.
|
||
asimpl. split.
|
||
- have h : rtc RPar.R (Proj PL (subst_Tm ρ a)) a0 by eauto using @relations.rtc_r.
|
||
have {}h : rtc RPar.R (subst_Tm (scons (Proj PL (subst_Tm ρ a)) ρ) B) (subst_Tm (scons a0 ρ) B) by eauto using substing_RPars.
|
||
move : hPB. asimpl.
|
||
eauto using InterpUnivN_back_preservation_star.
|
||
- hauto lq:on use:@relations.rtc_r, InterpUniv_back_clos_star.
|
||
Qed.
|