Goal:
  
  G : t
  HI : invariants G
  HG : acyclic_no_loop G
  y_0 : V.t
  x_0 : V.t
  Hxs : lsp G x_0 y_0 = None
  K : Z
  x : V.t
  ============================
   (weight (pathOf_refl G' x) =
    match from_G'_path (pathOf_refl G' x) with
    | inl q' => weight q'
    | inr (q1, q2) => weight q1 + K + weight q2
    end)


DEBUG:Going to execute:
fun => <coq-core.plugins.ltac::reflexivity@0>