1 (**************************************************************************)
4 (* ||A|| A project by Andrea Asperti *)
6 (* ||I|| Developers: *)
7 (* ||T|| The HELM team. *)
8 (* ||A|| http://helm.cs.unibo.it *)
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11 (* v GNU General Public License Version 2 *)
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15 include "static_2/syntax/ext2.ma".
17 (* EXTENSION TO BINDERS OF A RELATION FOR TERMS *****************************)
19 (* Main properties **********************************************************)
21 theorem ext2_trans: ∀R. Transitive … R → Transitive … (ext2 R).
22 #R #HR #I1 #I #H elim H -I1 -I
23 [ #I1 #J #H >(ext2_inv_unit_sn … H) -J /2 width=1 by ext2_unit/
24 | #I1 #V1 #V #HV1 #J #H elim (ext2_inv_pair_sn … H) -H
25 #V2 #HV2 #H destruct /3 width=3 by ext2_pair/