Theorem: LambdaCalculi.LambdaTerm.replace'_var (LambdaCalculi/LambdaCalculus.lean)

State before:
p : LambdaParams
U : Type u_1
C : Type u_2
f : ℕ → LambdaTerm p U C → Option (LambdaTerm p U C)
n m : ℕ
⊢ replace' f n (var m) =
    match f n (var m) with
    | some u => u
    | none => var m
Tactic:
simp only [replace']
State after:
no goals