3a457e6ad6
Many of our tests in `tests/lean/run/` produce output from `#eval` (or `#check`) statements, that is then ignored. This PR tries to capture all the useful output using `#guard_msgs`. I've only done a cursory check that the output is still sane --- there is a chance that some "unchecked" tests have already accumulated regressions and this just cements them! In the other direction, I did identify two rotten tests: * a minor one in `setStructInstNotation.lean`, where a comment says `Set Nat`, but `#check` actually prints `?_`. Weird? * `CompilerProbe.lean` is generating empty output, apparently indicating that something is broken, but I don't know the signficance of this file. In any case, I'll ask about these elsewhere. (This started by noticing that a recent `grind` test file had an untested `trace_state`, and then got carried away.)
39 lines
1.5 KiB
Text
39 lines
1.5 KiB
Text
/-!
|
||
# Verify that nested predicates don't trigger the generation of `below` lemmas
|
||
Since the case of nested predicates is not currently handled by `mkBelow` (in `src/Lean/Meta/IndPredBelow.lean`),
|
||
trying to generate `OnlyZeros.below` triggers an error upon defining the inductive type.
|
||
-/
|
||
|
||
inductive Forall (P : α → Prop) : List α → Prop
|
||
| nil : Forall P []
|
||
| cons : {x : α} → P x → Forall P l → Forall P (x::l)
|
||
|
||
inductive Tree : Type :=
|
||
| leaf : Nat → Tree
|
||
| node : List Tree → Tree
|
||
|
||
set_option trace.Meta.IndPredBelow true in
|
||
|
||
/-- info: [Meta.IndPredBelow] Nested or not recursive -/
|
||
#guard_msgs in
|
||
/-- Despite not having `.below` and `.brecOn`,
|
||
the type is still usable thanks to well-founded recursion. -/
|
||
inductive OnlyZeros : Tree → Prop :=
|
||
| leaf : OnlyZeros (.leaf 0)
|
||
| node (l : List Tree): Forall OnlyZeros l → OnlyZeros (.node l)
|
||
|
||
/-- Equivalent definition of `OnlyZeros`, defined by a function instead of an inductive type. -/
|
||
def onlyZeros : Tree → Prop
|
||
| .leaf n => n = 0
|
||
| .node [] => True
|
||
| .node (x::s) => onlyZeros x ∧ onlyZeros (.node s)
|
||
|
||
unseal onlyZeros in
|
||
/-- Pattern-matching on `OnlyZeros` works despite `below` and `brecOn` not being generated
|
||
if we make `onlyZeros` semireducible-/
|
||
def toFixPoint : OnlyZeros t → onlyZeros t
|
||
| .leaf => rfl
|
||
| .node [] _ => True.intro
|
||
| .node (x::s) (.cons h p) => by
|
||
rw [onlyZeros] -- necessary because `onlyZeros` isn't structurally recursive
|
||
exact And.intro (toFixPoint h) (toFixPoint (.node s p))
|