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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 *)
10 (* \ / This file is distributed under the terms of the *)
11 (* v GNU General Public License Version 2 *)
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15 include "lambda/paths/trace.ma".
16 include "basics/core_notation/card_1.ma".
18 (* DECOMPOSED TRACE *********************************************************)
20 (* Policy: decomposed trace metavariables: P, Q *)
21 (* Note: this is a binary tree on traces *)
22 inductive dtrace: Type[0] ≝
24 | tree_cons: trace → dtrace → dtrace → dtrace
27 let rec size (P:dtrace) on P ≝ match P with
29 | tree_cons s Q1 Q2 ⇒ size Q2 + size Q1 + |s|
32 interpretation "decomposed trace size" 'card P = (size P).