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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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15 include "delayed_updating/syntax/prototerm.ma".
16 include "delayed_updating/syntax/path_proper.ma".
17 include "ground/lib/subset_ext_equivalence.ma".
19 (* PROPER CONDITION FOR PROTOTERM *******************************************)
22 "proper condition (prototerm)"
23 'ClassP = (subset_ext_p1 path ppc).
25 (* Basic constructions ******************************************************)
28 (π β§ΈΟ΅ t) β t Ο΅ π.
33 (* Basic destructions *******************************************************)
35 lemma in_comp_tpc_trans (t) (p):
36 p Ο΅ t β t Ο΅ π β p Ο΅ π.
41 (* Basic inversions *********************************************************)
43 lemma tpc_inv_empty (t):
44 (π) Ο΅ t β t Ο΅ π β β₯.
45 /2 width=5 by in_comp_tpc_trans/ qed-.