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 "basic_2/i_dynamic/ntas_preserve.ma".
17 (* ITERATED NATIVE TYPE ASSIGNMENT FOR TERMS ********************************)
19 (* Main properties **********************************************************)
21 theorem ntas_trans (h) (a) (G) (L) (T0):
22 ∀n1,T1. ❨G,L❩ ⊢ T1 :*[h,a,n1] T0 →
23 ∀n2,T2. ❨G,L❩ ⊢ T0 :*[h,a,n2] T2 → ❨G,L❩ ⊢ T1 :*[h,a,n1+n2] T2.
24 #h #a #G #L #T0 #n1 #T1 * #X1 #HT0 #HT1 #H01 #H11 #n2 #T2 * #X2 #HT2 #_ #H22 #H02
25 elim (cnv_cpms_conf … HT0 … H01 … H02) -T0 <minus_O_n <minus_n_O #X0 #H10 #H20
26 /3 width=5 by ntas_intro, cpms_trans/