X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;ds=inline;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fdelayed_updating%2Freduction%2Fdfr.ma;h=193136433188b5857954573034cac434610a108e;hb=74223db3fc45caccb3cfac80971b29cb0613da28;hp=f0b3f5f319c56b603e94593c0355d2e8347df5ad;hpb=9605ffc88831066a901ea4eb8e419f277662f372;p=helm.git diff --git a/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma b/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma index f0b3f5f31..193136433 100644 --- a/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma +++ b/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma @@ -12,23 +12,23 @@ (* *) (**************************************************************************) -include "ground/xoa/ex_3_1.ma". -include "delayed_updating/syntax/path_structure.ma". -include "delayed_updating/syntax/path_balanced.ma". include "delayed_updating/substitution/fsubst.ma". -(* -include "delayed_updating/notation/functions/pitchforkleftarrow_3.ma". -*) +include "delayed_updating/syntax/prototerm_constructors.ma". +include "delayed_updating/syntax/prototerm_eq.ma". +include "delayed_updating/syntax/path_head.ma". +include "delayed_updating/syntax/path_depth.ma". +include "delayed_updating/syntax/path_reverse.ma". +include "delayed_updating/notation/relations/black_rightarrow_df_4.ma". -(* DELAYED FOCALIZED REDUCTION **********************************************) +(* DELAYED FOCUSED REDUCTION ************************************************) -inductive dfr (p) (q) (t): predicate preterm ≝ -| dfr_beta (b) (n): - let r ≝ p;;(𝗔;b;;(𝗟;q,𝗱❨n❩)) in - r ϵ t → ⊓⊗b → dfr p q t (t[⋔r←t⋔p,𝗦]) +definition dfr (p) (q): relation2 prototerm prototerm ≝ + λt1,t2. ∃n:pnat. + let r ≝ p●𝗔◗𝗟◗q in + ∧∧ (𝗟◗q)ᴿ = ↳[n](rᴿ) & r◖𝗱n ϵ t1 & + t1[⋔r←𝛕n.(t1⋔(p◖𝗦))] ⇔ t2 . -(* + interpretation - "focalized substitution (preterm)" - 'PitchforkLeftArrow t p u = (fsubst p u t). -*) + "focused reduction with delayed updating (prototerm)" + 'BlackRightArrowDF t1 p q t2 = (dfr p q t1 t2).