matita/matita/contribs/lambdadelta/basic_2/rt_transition/cpx_simple.ma

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  14
  15 include "basic_2/rt_transition/cpg_simple.ma".
  16 include "basic_2/rt_transition/cpx.ma".
  17
  18 (* EXTENDED CONTEXT-SENSITIVE PARALLEL RT-TRANSITION FOR TERMS **************)
  19
  20 (* Inversion lemmas with simple terms ***************************************)
  21
  22 lemma cpx_inv_appl1_simple (G) (L):
  23       ∀V1,T1,U. ❪G,L❫ ⊢ ⓐV1.T1 ⬈ U → 𝐒❪T1❫ →
  24       ∃∃V2,T2. ❪G,L❫ ⊢ V1 ⬈ V2 & ❪G,L❫ ⊢ T1 ⬈ T2 & U = ⓐV2.T2.
  25 #G #L #V1 #T1 #U * #c #H #HT1 elim (cpg_inv_appl1_simple … H) -H
  26 /3 width=5 by ex3_2_intro, ex_intro/
  27 qed-.