16 lines
309 B
Text
16 lines
309 B
Text
def g (x : Nat) := 2*x + 1
|
|
|
|
def f (x : Nat) : Nat :=
|
|
match g x with
|
|
| 0 => 1
|
|
| y + 1 => g x
|
|
|
|
example : f x = 2*x + 1 := by
|
|
unfold f
|
|
split
|
|
next h => simp_arith [g] at h
|
|
next y h =>
|
|
trace_state
|
|
-- split tactic should *not* rewrite `g x` to `Nat.succ y`
|
|
show g x = 2*x + 1
|
|
simp [g]
|