exact Or.inl $ Or.inr $ List.Sublist.subset preconditionProof f_in
case a
W : Type
L R : List Formula
O : Option (NegLoadFormula ⊕ NegLoadFormula)
M : KripkeModel W
w : W
Rcond : List Formula
ress : List (List Formula)
orule : OneSidedLocalRule Rcond ress
this osTruth : evaluate M w (Con Rcond) ↔ evaluate M w (discon ress)
preconditionProof : Rcond.Sublist R
w_LRO : (M, w)⊨(L, R, O)
f : Formula
f_in : f ∈ Rcond
⊢ (f ∈ L ∨ f ∈ R) ∨ f ∈ (Option.map (Sum.elim negUnload negUnload) O).toList
no goals