lean4-htt/tests/elab/structuralEqn6.lean
Garmelon 08eb78a5b2
chore: switch to new test/bench suite (#12590)
This PR sets up the new integrated test/bench suite. It then migrates
all benchmarks and some related tests to the new suite. There's also
some documentation and some linting.

For now, a lot of the old tests are left alone so this PR doesn't become
even larger than it already is. Eventually, all tests should be migrated
to the new suite though so there isn't a confusing mix of two systems.
2026-02-25 13:51:53 +00:00

87 lines
3.2 KiB
Text

def trailingZeros (i : Int) : Nat :=
if h : i = 0 then 0 else aux i.natAbs i h (Nat.le_refl _) 0
where
aux (k : Nat) (i : Int) (hi : i ≠ 0) (hk : i.natAbs ≤ k) (acc : Nat) : Nat :=
match k, (by omega : k ≠ 0) with
| k + 1, _ =>
if h : i % 2 = 0 then aux k (i / 2) (by omega) (by omega) (acc + 1)
else acc
termination_by structural k
/--
info: equations:
@[defeq] theorem trailingZeros.aux.eq_1 : ∀ (i : Int) (hi : i ≠ 0) (acc k_2 : Nat) (x_1 : k_2 + 1 ≠ 0)
(hk_2 : i.natAbs ≤ k_2 + 1),
trailingZeros.aux k_2.succ i hi hk_2 acc = if h : i % 2 = 0 then trailingZeros.aux k_2 (i / 2) ⋯ ⋯ (acc + 1) else acc
-/
#guard_msgs(pass trace, all) in
#print equations trailingZeros.aux
-- set_option trace.Elab.definition.eqns true
-- set_option trace.split.debug true
-- set_option trace.Meta.Match.unify true
def trailingZeros' (i : Int) : Nat :=
if h : i = 0 then 0 else aux i.natAbs i h (Nat.le_refl _) 0
where
aux (k : Nat) (i : Int) (hi : i ≠ 0) (hk : i.natAbs ≤ k) (acc : Nat) : Nat :=
match k, (by omega : k ≠ 0) with
| k + 1, _ =>
if h : i % 2 = 0 then aux k (i / 2) (by omega) (by omega) (acc + 1)
else acc
termination_by k
/--
info: equations:
theorem trailingZeros'.aux.eq_1 : ∀ (i : Int) (hi : i ≠ 0) (acc k_2 : Nat) (x_1 : k_2 + 1 ≠ 0)
(hk_2 : i.natAbs ≤ k_2 + 1),
trailingZeros'.aux k_2.succ i hi hk_2 acc =
if h : i % 2 = 0 then trailingZeros'.aux k_2 (i / 2) ⋯ ⋯ (acc + 1) else acc
-/
#guard_msgs(pass trace, all) in
#print equations trailingZeros'.aux
def trailingZeros2 (i : Int) : Nat :=
if h : i = 0 then 0 else aux i.natAbs i h (Nat.le_refl _) 0
where
aux (k : Nat) (i : Int) (hi : i ≠ 0) (hk : i.natAbs ≤ k) (acc : Nat) : Nat :=
match k with
| k + 1 =>
if h : i % 2 = 0 then aux k (i / 2) (by omega) (by omega) (acc + 1)
else acc
| 0 => by omega
termination_by structural k
/--
info: equations:
@[defeq] theorem trailingZeros2.aux.eq_1 : ∀ (i : Int) (hi : i ≠ 0) (acc k_2 : Nat) (hk_2 : i.natAbs ≤ k_2 + 1),
trailingZeros2.aux k_2.succ i hi hk_2 acc =
if h : i % 2 = 0 then trailingZeros2.aux k_2 (i / 2) ⋯ ⋯ (acc + 1) else acc
@[defeq] theorem trailingZeros2.aux.eq_2 : ∀ (i : Int) (hi : i ≠ 0) (acc : Nat) (hk_2 : i.natAbs ≤ 0),
trailingZeros2.aux 0 i hi hk_2 acc = acc
-/
#guard_msgs(pass trace, all) in
#print equations trailingZeros2.aux
def trailingZeros2' (i : Int) : Nat :=
if h : i = 0 then 0 else aux i.natAbs i h (Nat.le_refl _) 0
where
aux (k : Nat) (i : Int) (hi : i ≠ 0) (hk : i.natAbs ≤ k) (acc : Nat) : Nat :=
match k with
| k + 1 =>
if h : i % 2 = 0 then aux k (i / 2) (by omega) (by omega) (acc + 1)
else acc
| 0 => by omega
termination_by k
/--
info: equations:
theorem trailingZeros2'.aux.eq_1 : ∀ (i : Int) (hi : i ≠ 0) (acc k_2 : Nat) (hk_2 : i.natAbs ≤ k_2 + 1),
trailingZeros2'.aux k_2.succ i hi hk_2 acc =
if h : i % 2 = 0 then trailingZeros2'.aux k_2 (i / 2) ⋯ ⋯ (acc + 1) else acc
theorem trailingZeros2'.aux.eq_2 : ∀ (i : Int) (hi : i ≠ 0) (acc : Nat) (hk_2 : i.natAbs ≤ 0),
trailingZeros2'.aux 0 i hi hk_2 acc = acc
-/
#guard_msgs(pass trace, all) in
#print equations trailingZeros2'.aux