matita/matita/contribs/lambdadelta/basic_2/multiple/llor_ldrop.ma

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   3 (*      ||M||                                                             *)
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   5 (*      ||T||                                                             *)
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  10 (*       \ /        This file is distributed under the terms of the       *)
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  14
  15 include "basic_2/multiple/frees_lift.ma".
  16 include "basic_2/multiple/llor.ma".
  17
  18 (* POINTWISE UNION FOR LOCAL ENVIRONMENTS ***********************************)
  19
  20 (* Advanced properties ******************************************************)
  21
  22 lemma llor_skip: ∀L1,L2,U,d. |L1| ≤ |L2| → yinj (|L1|) ≤ d → L1 ⩖[U, d] L2 ≡ L1.
  23 #L1 #L2 #U #d #HL12 #Hd @and3_intro // -HL12
  24 #I1 #I2 #I #K1 #K2 #K #W1 #W2 #W #i #HLK1 #_ #HLK -I2 -L2 -K2
  25 lapply (ldrop_mono … HLK … HLK1) -HLK #H destruct
  26 lapply (ldrop_fwd_length_lt2 … HLK1) -K1
  27 /5 width=3 by ylt_yle_trans, ylt_inj, or3_intro0, and3_intro/
  28 qed.
  29
  30 axiom llor_total: ∀L1,L2,T,d. |L1| ≤ |L2| → ∃L. L1 ⩖[T, d] L2 ≡ L.