This PR allow structures to have non-bracketed binders, making it
consistent with `inductive`.
The change allows the following to be written instead of having to write
`S (n)`:
```lean
structure S n where
field : Fin n
```
This PR adds a `register_linter_set` command for declaring linter sets.
The `getLinterValue` function now checks if the present linter is
contained in a set that has been enabled (using the `set_option` command
or on the command line).
The implementation stores linter set membership in an environment
extension. As a consequence, we need to pass more data to
`getLinterValue`: the argument of ype `Options` has been replaced with a
`LinterOptions`, which you can access by writing `getLinterOptions`
instead of `getOptions`. (The alternative I considered is to modify the
`Options` structure. The current approach seems a bit higher-level and
lower-impact.)
The logic for checking whether a linter should be enabled now goes in
four steps:
1. If the linter has been explicitly en/disabled, return that.
2. If `linter.all` has been explicitly set, return that.
3. If the linter is in any set that has been enabled, return true.
4. Return the default setting for the linter.
Reasoning:
* The linter's explicit setting should take precedence.
* We want to be able to disable all but the explicitly enabled linters
with `linter.all`, so it should take precedence over linter sets.
* We want to progressively enable more linters as they become available,
so the check over sets should be *any*.
* Falling back to the default value last, ensures compatibility with the
current way we define linters.
The public-facing API currently does not allow modifying sets: all
linters have to be added when the set is declared. This way, there is
one place where all the contents of the set are listed.
Linter sets can be declared to contain linters that have not been
declared (yet): this allows declaring linter sets low down in the import
hierarchy when not all the requested linters are defined yet.
---------
Co-authored-by: grunweg <rothgami@math.hu-berlin.de>
This PR prefers using `∅` instead of `.empty` functions. We may later
rename `.empty` functions to avoid the naming clash with
`EmptyCollection`, and to better express semantics of functions which
take an optional capacity argument.
This PR moves away from using `List.get` / `List.get?` / `List.get!` and
`Array.get!`, in favour of using the `GetElem` mediated getters. In
particular it deprecates `List.get?`, `List.get!` and `Array.get?`. Also
adds `Array.back`, taking a proof, matching `List.getLast`.
This PR starts on the process of cleaning up variable names across
List/Array/Vector. For now, we just rename "numerical index" variables
in one file. This is driven by a custom linter.
This PR modifies structure instance notation and `where` notation to use
the same notation for fields. Structure instance notation now admits
binders, type ascriptions, and equations, and `where` notation admits
full structure lvals. Examples of these for structure instance notation:
```lean
structure PosFun where
f : Nat → Nat
pos : ∀ n, 0 < f n
def p : PosFun :=
{ f n := n + 1
pos := by simp }
def p' : PosFun :=
{ f | 0 => 1
| n + 1 => n + 1
pos := by rintro (_|_) <;> simp }
```
Just like for the structure `where` notation, a field `f x y z : ty :=
val` expands to `f := fun x y z => (val : ty)`. The type ascription is
optional.
The PR also is setting things up for future expansion. Pending some
discussion, in the future structure/`where` notation could have have
embedded `where` clauses; rather than `{ a := { x := 1, y := z } }` one
could write `{ a where x := 1; y := z }`.
This PR makes stricter requirements for the `@[deprecated]` attribute,
requiring either a replacement identifier as `@[deprecated bar]` or
suggestion text `@[deprecated "Past its use by date"]`, and also
requires a `since := "..."` field.
Should ensure we visit at most as many expr nodes as in the final expr
instead of many possibly overlapping mvar assignments. This is likely
the only way we can ensure acceptable performance in all cases.
---------
Co-authored-by: Kim Morrison <kim@tqft.net>
Deprecates `inductive ... :=`, `structure ... :=`, and `class ... :=` in
favor of the `... where` variant. Currently this syntax produces a
warning, controlled by the `linter.deprecated` option.
Breaking change: modifies `Lean.Linter.logLintIf` to use
`Lean.Linter.getLinterValue` to determine if a linter value is set. This
means that the `linter.all` option now is taken into account when the
linter option is not set.
Part of #5236
The `#guard_msgs` command runs the command it is attached to as if it
were a top-level command. This is because the top-level command
elaborator runs linters, and we are interested in capturing linter
warnings using `#guard_msgs`. However, the linters will run on
`#guard_msgs` itself, leading sometimes to duplicate warnings (like for
the unused variable linter).
Rather than special-casing `#guard_msgs` in every affected linter, this
PR special-cases it in the top-level command elaborator itself. **Now
linters are only run if the command doesn't contain `#guard_msgs`.**
This way, the linters are only run on the sub-command that `#guard_msgs`
runs itself. This rule also keeps linters from running multiple times in
cases such as `set_option pp.mvars false in /-- ... -/ #guard_msgs in
...`.
We need to follow the fvar aliases registered by `match` in both
directions
Fixes#4714, fixes#2837
---------
Co-authored-by: Mario Carneiro <di.gama@gmail.com>
This came up when watching new Lean users in a class situation. A number
of them were confused when they omitted a namespace on a constructor
name, and Lean treated the variable as a pattern that matches anything.
For example, this program is accepted but may not do what the user
thinks:
```
inductive Tree (α : Type) where
| leaf
| branch (left : Tree α) (val : α) (right : Tree α)
def depth : Tree α → Nat
| leaf => 0
```
Adding a `branch` case to `depth` results in a confusing message.
With this linter, Lean marks `leaf` with:
```
Local variable 'leaf' resembles constructor 'Tree.leaf' - write '.leaf' (with a dot) or 'Tree.leaf' to use the constructor.
note: this linter can be disabled with `set_option linter.constructorNameAsVariable false`
```
Additionally, the error message that occurs when invalid names are
applied in patterns now suggests similar names. This means that:
```
def length (list : List α) : Nat :=
match list with
| nil => 0
| cons x xs => length xs + 1
```
now results in the following warning on `nil`:
```
warning: Local variable 'nil' resembles constructor 'List.nil' - write '.nil' (with a dot) or 'List.nil' to use the constructor.
note: this linter can be disabled with `set_option linter.constructorNameAsVariable false`
```
and error on `cons`:
```
invalid pattern, constructor or constant marked with '[match_pattern]' expected
Suggestion: 'List.cons' is similar
```
The list of suggested constructors is generated before the type of the
pattern is known, so it's less accurate, but it truncates the list to
ten elements to avoid being overwhelming. This mostly comes up with
`mk`.
Complement to #3967 , adds a `(since := "<date>")` field to
`@[deprecated]` so that metaprogramming code has access to the
deprecation date for e.g. bulk removals. Also adds `@[deprecated
"deprecation message"]` to optionally replace the default text
"`{declName}` has been deprecated, use `{newName}` instead".
The `#guard_msgs` command already runs linters by virtue of using
`elabCommandTopLevel`, so linters should *not* be run on `#guard_msgs`
itself. While we could use a more general solution, of the linters the
unused variables linter is the noisiest one, and it's easy enough to
make it not report messages for `#guard_msgs`.
This fixes an issue where the completion would use info nodes before the
cursor for computing completions.
Fixes https://github.com/leanprover/lean4/issues/3462.
ToDo:
- [x] Fix test failures for completions that previously worked by
accident (cc: @Kha)
- [x] stage0 update
---------
Co-authored-by: Sebastian Ullrich <sebasti@nullri.ch>
This is a rewrite of the `UnusedVariables` lint to inline and simplify
many of the dependent functions to try to improve the performance of
this lint, which quite often shows up in perf reports.
* The mvar assignment scanning is one of the most expensive parts of the
process, so we do two things to improve this:
* Lazily perform the scan only if we need it
* Use an object-pointer hashmap to ensure that we don't have quadratic
behavior when there are many mvar assignments with slight differences.
* The dependency on `Lean.Server` is removed, meaning we don't need to
do the LSP conversion stuff anymore. The main logic of reference finding
is inlined.
* We take `fvarAliases` into account, and union together fvars which are
aliases of a base fvar. (It would be great if we had `UnionFind` here.)
More docs will be added once we confirm an actual perf improvement.
---------
Co-authored-by: Sebastian Ullrich <sebasti@nullri.ch>
- Add support for reserved declaration names. We use them for theorems
generated on demand.
- Equation theorems are not private declarations anymore.
- Generate equation theorems on demand when resolving symbols.
- Prevent users from creating declarations using reserved names. Users
can bypass it using meta-programming.
See next test for examples.
Fixes#1170.
This PR adds the module name to `RefIdent` in order to distinguish
conflicting names from different files. This also fixes related issues
in find-references or the call hierarchy feature.
It also adds some docstrings and stylistically refactors a bunch of
code.
This replaces the no-op `unusedVariablesIgnoreFnsExt` environment
extension with an actual environment extension which can be extended
using either `@[unused_variables_ignore_fn]` or
`@[builtin_unused_variables_ignore_fn]` (although for the present all
the builtin `unused_variables_ignore_fn`s are being added using direct
calls to `builtin_initialize addBuiltinUnusedVariablesIgnoreFn`, because
this also works and a stage0 update is required before the attribute can
be used).
We would like to use this attribute to disable unused variables in
syntaxes defined in std and mathlib, like
[`proof_wanted`](https://leanprover.zulipchat.com/#narrow/stream/113488-general/topic/Unused.20variables.20and.20proof_wanted/near/408554690).
