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15 include "basic_2/rt_computation/cpms_drops.ma".
16
17 (* CONTEXT-SENSITIVE PARALLEL R-COMPUTATION FOR TERMS ***********************)
18
19 (* Advanced inversion lemmas ************************************************)
20
21 (* Basic_1: was: pr3_gen_lref *)
22 (* Basic_2A1: was: cprs_inv_lref1 *)
23 lemma cprs_inv_lref1_drops (h) (G): ∀L,T2,i. ❪G,L❫ ⊢ #i ➡*[h,0] T2 →
24                                     ∨∨ T2 = #i
25                                      | ∃∃K,V1,T1. ⇩[i] L ≘ K.ⓓV1 & ❪G,K❫ ⊢ V1 ➡*[h,0] T1 &
26                                                   ⇧[↑i] T1 ≘ T2.
27 #h #G #L #T2 #i #H elim (cpms_inv_lref1_drops … H) -H *
28 [ /2 width=1 by or_introl/
29 | /3 width=6 by ex3_3_intro, or_intror/
30 | #m #K #V #V2 #_ #_ #_ #H destruct
31 ]
32 qed-.