matita/matita/contribs/lambdadelta/delayed_updating/syntax/path_balanced.ma

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  14
  15 include "delayed_updating/syntax/path.ma".
  16 include "delayed_updating/notation/functions/class_b_0.ma".
  17
  18 (* BALANCE CONDITION FOR PATH ***********************************************)
  19
  20 (* This condition applies to a structural path *)
  21 inductive pbc: predicate path ≝
  22 | pbc_empty: pbc (𝐞)
  23 | pbc_redex: ∀b. pbc b → pbc (𝗔◗b◖𝗟)
  24 | pbc_after: ∀b1,b2. pbc b1 → pbc b2 → pbc (b1●b2)
  25 .
  26
  27 interpretation
  28   "balance condition (path)"
  29   'ClassB = (pbc).