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4 (* ||A|| A project by Andrea Asperti *)
6 (* ||I|| Developers: *)
7 (* ||T|| The HELM team. *)
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15 include "Basic-2/grammar/term.ma".
17 (* WEIGHT OF A TERM *********************************************************)
19 let rec tw T ≝ match T with
21 | TPair _ V T ⇒ tw V + tw T + 1
24 interpretation "weight (term)" 'Weight T = (tw T).
26 (* Basic properties *********************************************************)
28 axiom tw_wf_ind: ∀R:term→Prop.
29 (∀T2. (∀T1. #[T1] < #[T2] → R T1) → R T2) →