matita/matita/contribs/lambdadelta/basic_2A/etc/delift/delift_ltpss.etc

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  14
  15 include "basic_2/unfold/ltpss_sn_alt.ma".
  16 include "basic_2/unfold/delift.ma".
  17
  18 (* INVERSE BASIC TERM RELOCATION  *******************************************)
  19
  20 (* Properties on sn partial unfold on local environments ********************)
  21
  22 lemma delift_ltpss_sn_conf_eq: ∀L,T1,T2,d,e. L ⊢ ▼*[d, e] T1 ≡ T2 →
  23                                ∀K. L ⊢ ▶* [d, e] K → K ⊢ ▼*[d, e] T1 ≡ T2.
  24 #L #T1 #T2 #d #e * #T #HT1 #HT2 #K #HLK
  25 elim (ltpss_sn_tpss_conf … HT1 … HLK) -HT1 -HLK #T0 #HT10 #HT0
  26 lapply (tpss_inv_lift1_eq … HT0 … HT2) -HT0 #H destruct /2 width=3/
  27 qed.
  28
  29 lemma ltpss_sn_delift_trans_eq: ∀L,K,d,e. L ⊢ ▶* [d, e] K →
  30                                 ∀T1,T2. K ⊢ ▼*[d, e] T1 ≡ T2 → L ⊢ ▼*[d, e] T1 ≡ T2.
  31 #L #K #d #e #HLK #T1 #T2 * #T #HT1 #HT2
  32 lapply (ltpss_sn_tpss_trans_eq … HT1 … HLK) -K /2 width=3/
  33 qed.