]> matita.cs.unibo.it Git - helm.git/blobdiff - matita/matita/contribs/lambdadelta/ground_2/steps/rtc.ma
syntactic components detached from basic_2 become static_2
[helm.git] / matita / matita / contribs / lambdadelta / ground_2 / steps / rtc.ma
index 494650d04d9dff70e6bff2054b0aa538d2613ef5..1e08d2474be31943ed50dcfd6fd1e55c50051768 100644 (file)
 (*                                                                        *)
 (**************************************************************************)
 
-include "ground_2/notation/constructors/tuple_4.ma".
-include "ground_2/notation/constructors/zerozero_0.ma".
-include "ground_2/notation/constructors/zeroone_0.ma".
-include "ground_2/notation/constructors/onezero_0.ma".
+include "ground_2/notation/functions/tuple_4.ma".
+include "ground_2/notation/functions/zerozero_0.ma".
+include "ground_2/notation/functions/zeroone_0.ma".
+include "ground_2/notation/functions/onezero_0.ma".
 include "ground_2/lib/arith.ma".
 
 (* RT-TRANSITION COUNTER ****************************************************)
 
 record rtc: Type[0] ≝ {
    ri: nat; (* Note: inner r-steps *)
-   rh: nat; (* Note: head  r-steps *)
+   rs: nat; (* Note: spine r-steps *)
    ti: nat; (* Note: inner t-steps *)
-   th: nat  (* Note: head  t-steps *)
+   ts: nat  (* Note: spine t-steps *)
 }.
 
 interpretation "constructor (rtc)"
-   'Tuple ri rh ti th = (mk_rtc ri rh ti th).
+   'Tuple ri rs ti ts = (mk_rtc ri rs ti ts).
 
 interpretation "one structural step (rtc)"
    'ZeroZero = (mk_rtc O O O O).
@@ -38,3 +38,29 @@ interpretation "one r-step (rtc)"
 
 interpretation "one t-step (rtc)"
    'ZeroOne = (mk_rtc O O O (S O)).
+
+definition eq_f: relation rtc ≝ λc1,c2. ⊤.
+
+inductive eq_t: relation rtc ≝
+| eq_t_intro: ∀ri1,ri2,rs1,rs2,ti,ts.
+              eq_t (〈ri1, rs1, ti, ts〉) (〈ri2, rs2, ti, ts〉)
+.
+
+(* Basic properties *********************************************************)
+
+lemma eq_t_refl: reflexive …  eq_t.
+* // qed.
+
+(* Basic inversion lemmas ***************************************************)
+
+fact eq_t_inv_dx_aux: ∀x,y. eq_t x y →
+                      ∀ri1,rs1,ti,ts. x = 〈ri1,rs1,ti,ts〉 →
+                      ∃∃ri2,rs2. y = 〈ri2,rs2,ti,ts〉.
+#x #y * -x -y
+#ri1 #ri #rs1 #rs #ti1 #ts1 #ri2 #rs2 #ti2 #ts2 #H destruct -ri2 -rs2
+/2 width=3 by ex1_2_intro/
+qed-.
+
+lemma eq_t_inv_dx: ∀ri1,rs1,ti,ts,y. eq_t (〈ri1,rs1,ti,ts〉) y →
+                   ∃∃ri2,rs2. y = 〈ri2,rs2,ti,ts〉.
+/2 width=5 by eq_t_inv_dx_aux/ qed-.