+++ /dev/null
-(**************************************************************************)
-(* ___ *)
-(* ||M|| *)
-(* ||A|| A project by Andrea Asperti *)
-(* ||T|| *)
-(* ||I|| Developers: *)
-(* ||T|| The HELM team. *)
-(* ||A|| http://helm.cs.unibo.it *)
-(* \ / *)
-(* \ / This file is distributed under the terms of the *)
-(* v GNU General Public License Version 2 *)
-(* *)
-(**************************************************************************)
-
-include "delayed_updating/unwind1/unwind.ma".
-include "delayed_updating/substitution/fsubst.ma".
-include "delayed_updating/syntax/prototerm_constructors.ma".
-include "delayed_updating/syntax/prototerm_equivalence.ma".
-include "delayed_updating/syntax/path_structure.ma".
-include "delayed_updating/syntax/path_balanced.ma".
-include "delayed_updating/syntax/path_depth.ma".
-include "delayed_updating/notation/relations/black_rightarrow_df_4.ma".
-include "ground/xoa/ex_1_2.ma".
-include "ground/xoa/and_4.ma".
-
-(* DELAYED FOCUSED REDUCTION ************************************************)
-
-definition dfr (p) (q): relation2 prototerm prototerm ≝
- λt1,t2. ∃∃b,n.
- let r ≝ p●𝗔◗b●𝗟◗q in
- ∧∧ (⊗b ϵ 𝐁 ∧ 𝟎 = ❘b❘) & ↑❘q❘ = (▼[r]𝐢)@❨n❩ & r◖𝗱n ϵ t1 &
- t1[⋔r←𝛗(n+❘b❘).(t1⋔(p◖𝗦))] ⇔ t2
-.
-
-interpretation
- "focused balanced reduction with delayed updating (prototerm)"
- 'BlackRightArrowDF t1 p q t2 = (dfr p q t1 t2).