+++ /dev/null
-(**************************************************************************)
-(* ___ *)
-(* ||M|| *)
-(* ||A|| A project by Andrea Asperti *)
-(* ||T|| *)
-(* ||I|| Developers: *)
-(* ||T|| The HELM team. *)
-(* ||A|| http://helm.cs.unibo.it *)
-(* \ / *)
-(* \ / This file is distributed under the terms of the *)
-(* v GNU General Public License Version 2 *)
-(* *)
-(**************************************************************************)
-
-include "basic_2/reducibility/crf.ma".
-
-(* CONTEXT-SENSITIVE IRREDUCIBLE TERMS **************************************)
-
-definition cif: lenv → predicate term ≝ λL,T. L ⊢ 𝐑⦃T⦄ → ⊥.
-
-interpretation "context-sensitive irreducibility (term)"
- 'NotReducible L T = (cif L T).
-
-(* Basic inversion lemmas ***************************************************)
-
-lemma cif_inv_delta: ∀L,K,V,i. ⇩[0, i] L ≡ K.ⓓV → L ⊢ 𝐈⦃#i⦄ → ⊥.
-/3 width=3/ qed-.
-
-lemma cif_inv_ri2: ∀I,L,V,T. ri2 I → L ⊢ 𝐈⦃②{I}V.T⦄ → ⊥.
-/3 width=1/ qed-.
-
-lemma cif_inv_ib2: ∀a,I,L,V,T. ib2 a I → L ⊢ 𝐈⦃ⓑ{a,I}V.T⦄ →
- L ⊢ 𝐈⦃V⦄ ∧ L.ⓑ{I}V ⊢ 𝐈⦃T⦄.
-/4 width=1/ qed-.
-
-lemma cif_inv_bind: ∀a,I,L,V,T. L ⊢ 𝐈⦃ⓑ{a,I}V.T⦄ →
- ∧∧ L ⊢ 𝐈⦃V⦄ & L.ⓑ{I}V ⊢ 𝐈⦃T⦄ & ib2 a I.
-#a * [ elim a -a ]
-[ #L #V #T #H elim (H ?) -H /3 width=1/
-|*: #L #V #T #H elim (cif_inv_ib2 … H) -H /2 width=1/ /3 width=1/
-]
-qed-.
-
-lemma cif_inv_appl: ∀L,V,T. L ⊢ 𝐈⦃ⓐV.T⦄ → ∧∧ L ⊢ 𝐈⦃V⦄ & L ⊢ 𝐈⦃T⦄ & 𝐒⦃T⦄.
-#L #V #T #HVT @and3_intro /3 width=1/
-generalize in match HVT; -HVT elim T -T //
-* // #a * #U #T #_ #_ #H elim (H ?) -H /2 width=1/
-qed-.
-
-lemma cif_inv_flat: ∀I,L,V,T. L ⊢ 𝐈⦃ⓕ{I}V.T⦄ →
- ∧∧ L ⊢ 𝐈⦃V⦄ & L ⊢ 𝐈⦃T⦄ & 𝐒⦃T⦄ & I = Appl.
-* #L #V #T #H
-[ elim (cif_inv_appl … H) -H /2 width=1/
-| elim (cif_inv_ri2 … H) -H /2 width=1/
-]
-qed-.
-
-(* Basic properties *********************************************************)
-
-lemma tif_atom: ∀I. ⋆ ⊢ 𝐈⦃⓪{I}⦄.
-/2 width=2 by trf_inv_atom/ qed.
-
-lemma cif_ib2: ∀a,I,L,V,T. ib2 a I → L ⊢ 𝐈⦃V⦄ → L.ⓑ{I}V ⊢ 𝐈⦃T⦄ → L ⊢ 𝐈⦃ⓑ{a,I}V.T⦄.
-#a #I #L #V #T #HI #HV #HT #H
-elim (crf_inv_ib2 … HI H) -HI -H /2 width=1/
-qed.
-
-lemma cif_appl: ∀L,V,T. L ⊢ 𝐈⦃V⦄ → L ⊢ 𝐈⦃T⦄ → 𝐒⦃T⦄ → L ⊢ 𝐈⦃ⓐV.T⦄.
-#L #V #T #HV #HT #H1 #H2
-elim (crf_inv_appl … H2) -H2 /2 width=1/
-qed.