matita/matita/contribs/lambdadelta/basic_2A/etc/fsup/fsup.etc

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  14
  15 include "basic_2/substitution/ldrop.ma".
  16
  17 (* SUPCLOSURE ***************************************************************)
  18
  19 (* Basic inversion lemmas ***************************************************)
  20
  21 fact fsup_inv_atom1_aux: ∀L1,L2,T1,T2. ⦃L1, T1⦄ ⊃ ⦃L2, T2⦄ → ∀J. T1 = ⓪{J} →
  22                          (∃∃I,K,V. L1 = K.ⓑ{I}V & J = LRef 0 & L2 = K & T2 = V) ∨
  23                          ∃∃I,K,V,i. ⦃K, #i⦄ ⊃ ⦃L2, T2⦄ & L1 = K.ⓑ{I}V & J = LRef (i+1).
  24 #L1 #L2 #T1 #T2 * -L1 -L2 -T1 -T2
  25 [ #I #L #V #J #H destruct /3 width=6/
  26 | #I #L #K #V #T #i #HLK #J #H destruct /3 width=7/
  27 | #a #I #L #V #T #J #H destruct
  28 | #a #I #L #V #T #J #H destruct
  29 | #I #L #V #T #J #H destruct
  30 | #I #L #V #T #J #H destruct
  31 ]
  32 qed-.
  33
  34 lemma fsup_inv_atom1: ∀J,L1,L2,T2. ⦃L1, ⓪{J}⦄ ⊃ ⦃L2, T2⦄ →
  35                       (∃∃I,K,V. L1 = K.ⓑ{I}V & J = LRef 0 & L2 = K & T2 = V) ∨
  36                       ∃∃I,K,V,i. ⦃K, #i⦄ ⊃ ⦃L2, T2⦄ & L1 = K.ⓑ{I}V & J = LRef (i+1).
  37 /2 width=3 by fsup_inv_atom1_aux/ qed-.
  38
  39 fact fsup_inv_bind1_aux: ∀L1,L2,T1,T2. ⦃L1, T1⦄ ⊃ ⦃L2, T2⦄ →
  40                          ∀b,J,W,U. T1 = ⓑ{b,J}W.U →
  41                          (L2 = L1 ∧ T2 = W) ∨
  42                          (L2 = L1.ⓑ{J}W ∧ T2 = U).
  43 #L1 #L2 #T1 #T2 * -L1 -L2 -T1 -T2
  44 [ #I #L #V #b #J #W #U #H destruct
  45 | #I #L #K #V #T #i #_ #b #J #W #U #H destruct
  46 | #a #I #L #V #T #b #J #W #U #H destruct /3 width=1/
  47 | #a #I #L #V #T #b #J #W #U #H destruct /3 width=1/
  48 | #I #L #V #T #b #J #W #U #H destruct
  49 | #I #L #V #T #b #J #W #U #H destruct
  50 ]
  51 qed-.
  52
  53 lemma fsup_inv_bind1: ∀b,J,L1,L2,W,U,T2. ⦃L1, ⓑ{b,J}W.U⦄ ⊃ ⦃L2, T2⦄ →
  54                       (L2 = L1 ∧ T2 = W) ∨
  55                       (L2 = L1.ⓑ{J}W ∧ T2 = U).
  56 /2 width=4 by fsup_inv_bind1_aux/ qed-.
  57
  58 fact fsup_inv_flat1_aux: ∀L1,L2,T1,T2. ⦃L1, T1⦄ ⊃ ⦃L2, T2⦄ →
  59                          ∀J,W,U. T1 = ⓕ{J}W.U →
  60                          L2 = L1 ∧ (T2 = W ∨ T2 = U).
  61 #L1 #L2 #T1 #T2 * -L1 -L2 -T1 -T2
  62 [ #I #L #K #J #W #U #H destruct
  63 | #I #L #K #V #T #i #_ #J #W #U #H destruct
  64 | #a #I #L #V #T #J #W #U #H destruct
  65 | #a #I #L #V #T #J #W #U #H destruct
  66 | #I #L #V #T #J #W #U #H destruct /3 width=1/
  67 | #I #L #V #T #J #W #U #H destruct /3 width=1/
  68 ]
  69 qed-.
  70
  71 lemma fsup_inv_flat1: ∀J,L1,L2,W,U,T2. ⦃L1, ⓕ{J}W.U⦄ ⊃ ⦃L2, T2⦄ →
  72                       L2 = L1 ∧ (T2 = W ∨ T2 = U).
  73 /2 width=4 by fsup_inv_flat1_aux/ qed-.