CategoryAnswerLinter.lean`

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4 declarations, 1 contain sorry, 0 declared as axioms

The Category Answer Linter

The CategoryAnswerLinter ensures that declarations tagged @[category research solved] do not leave answer(sorry) in their statement: once a problem is solved, the answer should be filled in explicitly, e.g. answer(True).

The check is syntactic. Under the default google.answer setting, answer(sorry) at Prop elaborates to a bare True carrying no annotation, so the placeholder is no longer visible in the elaborated term.

A statement that deliberately keeps answer(sorry) (for instance because the problem is independent of ZFC, or because the answer is a constant that is not known explicitly) can opt out with set_option linter.style.category_answer false in.

Imports (3)

Imported by 2 files

def CategoryAnswerLinter.containsSorry Whether stx contains a sorry anywhere sorry line 49 source
Source documentation
Whether stx contains a sorry anywhere.

no axioms what this means
Statement uses: Lean.Syntax, Bool
Proof uses: Inhabited.default
1 instances, coercions and auxiliary constants left out.
```
partial def containsSorry (stx : Syntax) : Bool :=
…
```
def CategoryAnswerLinter.answerSorries The answer(..) nodes in stx whose answer is still a sorry line 53 source
Source documentation
The answer(..) nodes in stx whose answer is still a sorry.

no axioms what this means
Statement uses: Lean.Syntax, Array
Proof uses: Inhabited.default
1 instances, coercions and auxiliary constants left out.
```
partial def answerSorries (stx : Syntax) : Array Syntax :=
…
```
def CategoryAnswerLinter.categoryNeedsAnswer Whether the given category is research solved line 58 source
Source documentation
Whether the given category is research solved.

standard axioms: propext what this means
Statement uses: ProblemAttributes.Category, Bool
Proof uses: BEq.beq, ProblemAttributes.Category.research, ProblemAttributes.ProblemStatus.solved
1 instances, coercions and auxiliary constants left out.
```
def categoryNeedsAnswer (cat : ProblemAttributes.Category) : Bool :=
…
```
Mentions: ProblemAttributes.Category
def CategoryAnswerLinter.categoryAnswerLinter The linter checking that solved statements do not use answer(sorry) line 62 source
Source documentation
The linter checking that solved statements do not use answer(sorry).

standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses: Lean.Elab.Command.Linter
Proof uses: Lean.Elab.Command.Linter.mk, Lean.withSetOptionIn, Lean.Syntax, ite, Lean.Elab.Command.CommandElabM, Unit, Eq, Bool, Lean.Syntax.isOfKind, Lean.Name.mkStr4, Bool.true, Lean.Syntax.getArg, OfNat.ofNat, Nat, cond, Bool.or, Bool.false, Lean.TSyntax, List.cons, Lean.SyntaxNodeKind and 36 more
16 instances, coercions and auxiliary constants left out.
```
def categoryAnswerLinter : Linter where
…
```