This PR improves the API for invariants and postconditions and as such
introduces a few breaking changes to the existing pre-release API around
`Std.Do`. It also adds Markus Himmel's `pairsSumToZero` example as a
test case.
This PR changes the IR RC pass to take "implied borrows" from
projections into account. If a projected value's lifetime is contained
in that of its parent (or any projection ancestor), then it does not
need its reference count incremented (or later decremented).
I believe that this same technique should generalize to both the
reset/reuse and borrow signature inference passes.
This PR splits out an implementation detail of
MVarId.getMVarDependencies into a top-level function. Aesop was relying
on the function defined in the where clause, which is no longer possible
after #9759.
This PR modifies the pretty printing of anonymous metavariables to use
the index rather than the internal name. This leads to smaller numerical
suffixes in `?m.123` since the indices are numbered within a given
metavariable context rather than across an entire file, hence each
command gets its own numbering. This does not yet affect pretty printing
of universe level metavariables.
For debugging purposes, metavariables that are not defined now pretty
print as `?_mvar.123` rather than cause pretty printing to fail.
This PR combines the simplification and unfold-reducible-constants steps
in `grind` to ensure that no potential normalization steps are missed.
Closes#9610
This PR fixes a bug in the projection over constructor propagator used
in `grind`. It may construct type incorrect terms when a equivalence
class contains heterogeneous equalities.
closes#9769
We compute the liveness information for the join point body, so the only
thing that updateJPLiveVarMap should be adding is the binding of the
params, which we can easily do ourselves.
If we supported recursive join points, I believe this would actually be
a correctness issue, but as-is it doesn't affect the output.
This PR fixes the documentation of the pipe operator |>, which is
currently (emphasis mine):
> Haskell-like pipe operator `|>`. `x |> f` means **the same as the same
as** `f x`,
> and it chains such that `x |> f |> g` is interpreted as `g (f x)`.
This PR implements the option `mvcgen +jp` to employ a slightly lossy VC
encoding for join points that prevents exponential VC blowup incurred by
naïve splitting on control flow.
```lean
def ifs_pure (n : Nat) : Id Nat := do
let mut x := 0
if n > 0 then x := x + 1 else x := x + 2
if n > 1 then x := x + 3 else x := x + 4
if n > 2 then x := x + 1 else x := x + 2
if n > 3 then x := x + 1 else x := x + 2
if n > 4 then x := x + 1 else x := x + 2
if n > 5 then x := x + 1 else x := x + 2
return x
theorem ifs_pure_triple : ⦃⌜True⌝⦄ ifs_pure n ⦃⇓ r => ⌜r > 0⌝⦄ := by
unfold ifs_pure
mvcgen +jp
/-
...
h✝⁵ : if n > 0 then x✝⁵ = 0 + 1 else x✝⁵ = 0 + 2
h✝⁴ : if n > 1 then x✝⁴ = x✝⁵ + 3 else x✝⁴ = x✝⁵ + 4
h✝³ : if n > 2 then x✝³ = x✝⁴ + 1 else x✝³ = x✝⁴ + 2
h✝² : if n > 3 then x✝² = x✝³ + 1 else x✝² = x✝³ + 2
h✝¹ : if n > 4 then x✝¹ = x✝² + 1 else x✝¹ = x✝² + 2
h✝ : if n > 5 then x✝ = x✝¹ + 1 else x✝ = x✝¹ + 2
⊢ x✝ > 0
-/
grind
```
This PR does what #9234 regrettably failed to do: actually reintroduce
the signatures of some `Subarray` functions that are now implemented via
slices (see #9017) in order to ensure backward compatibility and
consistency. With this PR, the old interface is restored. As an added
benefit, `Subarray.forIn` is no longer opaque.
This PR re-implements `IO.waitAny` using Lean instead of C++. This is to
reduce the size and
complexity of `task_manager` in order to ease future refactorings.
There is an import behavioral change of `IO.waitAny` in this PR.
Consider a situation where we have
two promises `p1`, `p2` and call `IO.waitAny [p1.result!, p2.result!]`
and `p1` resolves instantly.
Previously this would just return the result of `p1` and require nothing
else. With the new
implementation if `p2` is released before being resolved this can cause
a panic, even if
`IO.waitAny` has already finished. I argue that this is reasonable
behavior, given that an
invocation of `result!` promises that the promise will eventually be
resolved.