This PR renames the member `insert_emptyc_eq` of the `LawfulSingleton`
typeclass to `insert_empty_eq` to conform to the recommended spelling of
`∅` as `empty`.
See also #7447.
This PR changes the syntax of location modifiers for tactics like `simp`
and `rw` (e.g., `simp at h ⊢`) to allow the turnstile `⊢` to appear
anywhere in the sequence of locations.
Closes#2278.
This PR implements the bitwuzla rule
[`BV_CONCAT_EXTRACT`](https://github.com/bitwuzla/bitwuzla/blob/main/src/rewrite/rewrites_bv.cpp#L1146-L1176).
This will be used by the bitblaster to simplify adjacent `extract`s
into a single `extract`.
We also implement the negated version of the rule,
which allows adjacent `not (extractLsb' _)` to be simplified into a
single `not (extractLsb' _)`.
This PR adds `BitVec.[toNat|toFin|toInt]_[sshiftRight|sshiftRight']`
plus variants with `of_msb_*`. While at it, we also add
`toInt_zero_length` and `toInt_of_zero_length`. In support of our main
theorem we add `toInt_shiftRight_lt` and `le_toInt_shiftRight`, which
make the main theorem automatically derivable via omega.
We also add four shift lemmas for `Int`: `le_shiftRight_of_nonpos`,
`shiftRight_le_of_nonneg`, `le_shiftRight_of_nonneg`,
`shiftRight_le_of_nonpos`, as well as `emod_eq_add_self_emod`,
`ediv_nonpos_of_nonpos_of_neg `, and`bmod_eq_emod_of_lt `. For `Nat` we
add `shiftRight_le`.
Beyond the lemmas directly needed in the proof, we added a couple more
to ensure the API is complete.
We also fix the casing of `toFin_ushiftRight` and rename `lt_toInt` to
`two_mul_lt_toInt` to avoid `'`-ed lemmas.
This PR makes the instance for `Subsingleton (Squash α)` work for `α :
Sort u`.
Closes#7405
The fix removes some unused `section`/`variable` commands. They were
mistakenly kept when `EqvGen` was removed in 1d338c4.
This PR adds definitions that will be required to allow to appear
turnstiles anywhere in tactic location specifiers.
This is the first (pre-stage0 update) half of #6992.
This PR adds the Bitwuzla rewrite rule
[`BV_EXTRACT_FULL`](6a1a768987/src/rewrite/rewrites_bv.cpp (L1236-L1253)),
which is useful for the bitblaster to simplify `extractLsb'` based
expressions.
```lean
theorem extractLsb'_eq_self (x : BitVec w) : x.extractLsb' 0 w = x
```
This PR adds lemmas for iterated conversions between finite types,
starting with something of type `Nat`/`Int`/`Fin`/`BitVec` and going
through `IntX`.
This PR allows the use of `dsimp` during preprocessing of well-founded
definitions. This fixes regressions when using `if-then-else` without
giving a name to the condition, but where the condition is needed for
the termination proof, in cases where that subexpression is reachable
only by dsimp, but not by simp (e.g. inside a dependent let)
Also fixes some preprocessing lemmas to not be bad simp lemmas (with
lambdas on the LHS, due to dot notation and unfortunate argument order)
This fixes#7408.
This PR uses `-implicitDefEqProofs` in `bv_omega` to ensure it is not
affected by the change in #7386.
---------
Co-authored-by: Leonardo de Moura <leomoura@amazon.com>
This PR makes the docstrings in the `Char` namespace follow the
documentation conventions.
---------
Co-authored-by: Markus Himmel <markus@himmel-villmar.de>
This PR fixes an issue in the `grind` tactic when case splitting on
if-then-else expressions.
It adds a new marker gadget that prevents `grind` for re-normalizing the
condition `c` of an if-then-else
expression. Without this marker, the negated condition `¬c` might be
rewritten into
an alternative form `c'`, which `grind` may not recognize as equivalent
to `¬c`.
As a result, `grind` could fail to propagate that `if c then a else b`
simplifies to `b`
in the `¬c` branch.
This PR adds lemmas about `Int` that will be required in #7368.
Most notably, we add
```lean
@[simp] theorem neg_nonpos_iff (i : Int) : -i ≤ 0 ↔ 0 ≤ i
```
which causes some breakage but gets us closer to mathlib which has a
more general version of this that applies to `Int`.
Note also that the mathlib adaptation branch deletes the (unused in
mathlib) mathib lemma `Int.zero_le_ofNat` as there is now a
syntactically different (but definitionally equal) `Int.zero_le_ofNat`
in core.
This PR fills further gaps in the integer division API, and mostly
achieves parity between the three variants of integer division. There
are still some inequality lemmas about `tdiv` and `fdiv` that are
missing, but as they would have quite awkward statements I'm hoping that
for now no one is going to miss them.
This PR ensures cutsat does not have to perform case analysis in the
univariate polynomial case. That it, it can close a goal whenever there
is no solution for a divisibility constraint in an interval. Example of
theorem that is now proved in a single step by cutsat:
```lean
example (x : Int) : 100 ≤ x → x ≤ 10000 → 20000 ∣ 3*x → False := by
grind
```
This PR implements cooper conflict resolution in the cutsat procedure.
It also fixes several bugs in the proof term construction. We still need
to add more tests, but we can already solve the following example that
`omega` fails to solve:
```lean
example (x y : Int) :
27 ≤ 11*x + 13*y →
11*x + 13*y ≤ 45 →
-10 ≤ 7*x - 9*y →
7*x - 9*y ≤ 4 → False := by
grind
```
This PR continues alignment of lemmas about `Int.ediv/fdiv/tdiv`,
including adding notes about "missing" lemmas that do not apply in one
case. Also lemmas about `emod/fmod/tmod`. There's still more to do.