cases b
f : Bool → Bool → Bool
f_stable : f false false = false
n : Nat
hfft : f false true = true
b : Bool
⊢ f false b = b
case false
f : Bool → Bool → Bool
f_stable : f false false = false
n : Nat
hfft : f false true = true
⊢ f false false = false

case true
f : Bool → Bool → Bool
f_stable : f false false = false
n : Nat
hfft : f false true = true
⊢ f false true = true