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partial update in static_2
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14
15 include "static_2/notation/functions/weight_1.ma".
16 include "static_2/syntax/term.ma".
17
18 (* WEIGHT OF A TERM *********************************************************)
19
20 rec definition tw T ≝ match T with
21 [ TAtom _     ⇒ 1
22 | TPair _ V T ⇒ ↑(tw V + tw T)
23 ].
24
25 interpretation "weight (term)" 'Weight T = (tw T).
26
27 (* Basic properties *********************************************************)
28
29 (* Basic_1: was: tweight_lt *)
30 lemma tw_pos: ∀T. 1 ≤ ♯❨T❩.
31 #T elim T -T //
32 qed.
33
34 lemma tw_le_pair_dx (I): ∀V,T. ♯❨T❩ < ♯❨②[I]V.T❩.
35 #I #V #T /2 width=1 by nle_succ_bi/
36 qed.
37
38 (* Basic_1: removed theorems 11:
39             wadd_le wadd_lt wadd_O weight_le weight_eq weight_add_O
40             weight_add_S tlt_trans tlt_head_sx tlt_head_dx tlt_wf_ind
41 *)
42 (* Basic_1: removed local theorems 1: q_ind *)