This PR improves match compilation: Branch on variables in the order
suggested by the first remaining alternative, and do not branch when the
first remaining alternative does not require it. This fixes
https://github.com/leanprover/lean4/issues/10749. With `set_option
backwards.match.rowMajor false` the old behavior can be turned on.
(For now this is an experiment to get familiar with the code and the
whole
problem domain. It is likely overly naive.)
This PR extracts some refactorings from #10763, including dropping dead
code and not failing in `inaccessibleAsCtor`, which leadas to (slightly)
better error messages, and also on the grounds that the failing
alternative may actually be unreachable.
This PR adds support for specifying anchors to restrict the search space
in `grind` when using `grind only`. Anchors can limit which case splits
are performed and which local lemmas are instantiated.
This PR tries to preserve names of pattern variables in match
alternatives in `decreasing_by`, by telescoping into the concrete
alternative rather than the type of the matcher's alt. Fixes#10976.
This PR implements the following `grind` improvements:
1. `set_option` can now be used to set `grind` configuration options in
the interactive mode.
2. Fixes a bug in the repeated theorem instantiation detection.
3. Adds the macro `use [...]` as a shorthand for `instantiate only
[...]`.
This PR adds the combinator ` · t_1 ... t_n` to the `grind` interactive
mode. The `finish?` tactic now generates scripts using this combinator
to conform to Mathlib coding standards. The new format is also more
compact. Example:
```lean
/--
info: Try this:
[apply] ⏎
instantiate only [= mem_indices_of_mem, insert, = getElem_def]
instantiate only [= getElem?_neg, = getElem?_pos]
cases #f590
· cases #ffdf
· instantiate only
instantiate only [= Array.getElem_set]
· instantiate only
instantiate only [size, = HashMap.mem_insert, = HashMap.getElem_insert, = Array.getElem_push]
· instantiate only [= mem_indices_of_mem, = getElem_def]
instantiate only [usr getElem_indices_lt]
instantiate only [size]
cases #ffdf
· instantiate only [=_ WF]
instantiate only [= getElem?_neg, = getElem?_pos, = Array.getElem_set]
instantiate only [WF']
· instantiate only
instantiate only [= HashMap.mem_insert, = HashMap.getElem_insert, = Array.getElem_push]
-/
#guard_msgs in
example (m : IndexMap α β) (a a' : α) (b : β) (h : a' ∈ m.insert a b) :
(m.insert a b)[a'] = if h' : a' == a then b else m[a'] := by
grind => finish?
```
This PR ensures that model-based theory combination in `grind cutsat`
considers nonlinear terms. Nonlinear multiplications such as `x * y` are
treated as uninterpreted symbols in `cutsat`.
Closes#10885
This PR adds support for scientific literals for `Rat` in `grind`.
`grind` does not yet add support for this kind of literal in arbitrary
fields.
closes#10489
This PR fixes a bug in the equality propagation procedure in
`grind.order`. Specifically, it affects the procedure that asserts
equalities in the `grind` core state that are implied by (ring)
inequalities in the `grind.order` module.
closes#10622
This is a guard against #10705; if a kernel error is raised when the
return value of this function is eventually checked, it is often
silenced downstream, making it hard to spot the failure.
If we panic here via `assert!`, then the diagnostic cannot be missed.
This PR adds the `mbtc` tactic to the `grind` interactive mode. It
implements model-based theory combination. It also ensures `finish?` is
capable of generating it.
This PR ensures that solver propagation steps are necessary in the
generated tactic script to close the goal.
It produces more compact proof scripts, but this is not just an
optimization, if we include an unnecessary step, we may fail to replay
the generated script when `cases` steps are pruned using
non-chronological backtracking (NCB). For example, when executing
`finish?`, we may have performed a `cases #<anchor>` step that enabled
`ring` to propagate a new fact. If this fact is not used in the final
proof, and the corresponding `cases #<anchor>` step is pruned by NCB,
the `ring` step will fail during replay.
This PR ensures that `finish?` produces partial tactic scripts
containing `sorry`s.
We may add an option to disable this feature in the future.
It is enabled by default because it provides a useful way to debug
`grind` failures.
This PR topologically sorts abstracted vars in
`Meta.Closure.mkValueTypeClosure` if MVars are being abstracted.
Fixes#10705
---------
Co-authored-by: Eric Wieser <efw@google.com>
This PR fixes another instance of the “default parameter value in
constructor” footgun, which was affecting the `cases` tactic in the
`grind` interactive mode.
This PR implements the `have <ident>? : <prop>` tactic for the `grind`
interactive mode. The proposition is proved using the default `grind`
search strategy. This tactic is also useful for inspecting or querying
the current `grind` state.
This PR implements parameter optimization for the generated
`instantiate` tactics produced by `finish?`.
We use a simple parameter optimizer that takes two sets as input: the
lower and upper bounds.
The lower bound consists of the theorems actually used in the proof
term, while the upper bound includes all the theorems instantiated in a
particular theorem instantiation step.
The lower bound is often sufficient to replay the proof, but in some
cases, additional theorems must be included because a theorem
instantiation may contribute to the proof by providing terms and many
not be present in the final proof term.
This PR optimizes two `String` proofs and makes sure that
`MkIffOfInductiveProp` does not import `Lean.Elab.Tactic`, which
previously pushed it to the very end of the import graph.
This PR fixes a proof instability source in `grind`.
We say a proof is *unstable* if minor changes in the `.lean` file
containing the proof **affect** it.
This PR renames `String.endPos` to `String.rawEndPos`, as in a future
release the name `String.endPos` will be taken by the function that is
currently called `String.endValidPos`.
This PR lets match compilation use exfalso as soon as no alternatives
are left. This way, the compiler does not have to look at subsequent
case splits.
This PR improves the `grind` tactic generated by the `instantiate`
action in tracing mode. It also updates the syntax for the `instantiate`
tactic, making it similar to `simp`. For example:
* `instantiate only [thm1, thm2]` instantiates only theorems `thm1` and
`thm2`.
* `instantiate [thm1, thm2]` instantiates theorems marked with the
`@[grind]` attribute **and** theorems `thm1` and `thm2`.
The action produces `instantiate only [...]` tactics. Example:
```lean
/--
info: Try this:
[apply] ⏎
instantiate only [= Array.getElem_set]
instantiate only [= Array.getElem_set]
-/
#guard_msgs in
example (as bs cs : Array α) (v₁ v₂ : α)
(i₁ i₂ j : Nat)
(h₁ : i₁ < as.size)
(h₂ : bs = as.set i₁ v₁)
(h₃ : i₂ < bs.size)
(h₄ : cs = bs.set i₂ v₂)
(h₅ : i₁ ≠ j ∧ i₂ ≠ j)
(h₆ : j < cs.size)
(h₇ : j < as.size) :
cs[j] = as[j] := by
grind => finish?
```
Recall that `finish?` replays generated tactics before suggesting them.
The `instantiate` action inspects the generated proof term to decide
which theorems to include as parameters in the `instantiate only [...]`
tactic. However, in some cases, a theorem contributes only by adding a
term to the state. In such cases, the generated tactic cannot be fully
replayed, and the action uses
`instantiate approx [<thms instantiated>]` to indicate which parts of
the tactic script are approximate. The `approx` is just a hint for
users.
This PR implements the `finish?` tactic for the `grind` interactive
mode. When it successfully closes the goal, it produces a code action
that allows the user to close the goal using explicit grind tactic
steps, i.e., without any search. It also makes explicit which solvers
have been used.
This is just the first version, we will add many "bells and whistles"
later. For example, `instantiate` steps will clearly show which theorems
have been instantiated.
Example:
```lean
/--
info: Try this:
[apply] ⏎
cases #b0f4
next => cases #50fc
next => cases #50fc <;> lia
-/
#guard_msgs in
example (p : Nat → Prop) (x y z w : Int) :
(x = 1 ∨ x = 2) →
(w = 1 ∨ w = 4) →
(y = 1 ∨ (∃ x : Nat, y = 3 - x ∧ p x)) →
(z = 1 ∨ z = 0) → x + y ≤ 6 := by
grind => finish?
```
The anchors in the generated script are based on stable hash codes.
Moreover, users can hover over them to see the exact term used in the
case split. `grind?` will also be implemented using the new framework.
This PR implements support for `Action` in the `grind` solver extensions
(`SolverExtension`). It also provides the `Solvers.mkAction` function
that constructs an `Action` using all registered solvers. The generated
action is "fair," that is, a solver cannot prevent other solvers from
making progress.
This PR implements infrastructure for evaluating `grind` tactics in the
`GrindM` monad. We are going to use it to check whether auto-generated
tactics can effectively close the original goal.
This PR moves many operations involving `String.Pos.Raw` to a the
`String.Pos.Raw` namespace with the eventual aim of freeing up the
`String` namespace to contain operations using `String.ValidPos` (to be
renamed to `String.Pos`) instead.
This PR adds the `String.ValidPos.set` and `String.ValidPos.modify`
functions.
After this PR, `String.pos_lt_eq` is no longer a `simp` lemma. Add
`String.Pos.Raw.lt_iff` as a `simp` lemma if your proofs break.
This PR implements a compact notation for inspecting the `grind` state
in interactive mode. Within a `grind` tactic block, each tactic may
optionally have a suffix of the form `| filter?`.
Examples:
```lean
instantiate | gen > 0 -- Displays terms in the `grind` state after executing `instantiate` with generation greater than zero
```
```lean
instantiate | -- Displays the `grind` state after executing `instantiate`
```
Remark: If the user places the cursor one space before `|`, the state
*before* executing `instantiate` is displayed.
This PR removes the code that was silently displaying the `grind` state
after each tactic step, as it was too noisy.
It also updates the notation for the `first` combinator in the `grind`
tactic mode to avoid conflicts with the new syntax.
This PR changes match compilation to reject some pattern matches that
were previously accepted due to inaccessible patterns sometimes treated
like accessible ones. Fixes#10794.
