AnswerLinter.lean`

Explanation legend Lean4 Domain Explanation Language (L4DEL)

L4DEL explanations are a separate layer. They do not change the Lean source. Intuition is explanatory prose; numbered items are a reading path; sources link the wording back to evidence.

L4DEL: Lean4 Domain Explanation Language

Annotation provenance. This overlay contains 10 curated AI-written annotations and 7190 mechanical source-derived annotations. They have not been human-reviewed as explanations; treat them as unverified and not mathematical authority. Retained generation history: The 71 original curated annotations were produced in a Claude Sonnet 5.5 session at medium effort; Claude Opus 5.5 is recorded in that session as the advisor model, not the direct author. The bulk source-derived expansion was generated mechanically from pinned source comments by tooling developed in a GPT-5.6 Sol session at ultra reasoning; GPT-5.6 Sol did not originate the quoted source prose. On 2026-10-17 the mechanically generated source-comment annotations of the Formal Conjectures, Carleson, FLT, PFR, CompFiles, Mathematics in Lean and Theorem Proving in Lean overlays were regenerated by the same generator after three corrections made in a Claude Sonnet 5.5 session: titles no longer cut a sentence inside mathematics or end on a dangling word, workflow markers are removed from the quoted prose, and declaration names follow the scanner's namespace resolution. The boilerplate step line was dropped, and comments that were only a row of dashes no longer yield annotations. No new prose was written and no human review is claimed.

Credit: The upstream authors and contributors retain credit for the project and mathematics. lean4-explainer only renders their pinned source and adds the separately disclosed explanation layer.

Project sources: Pinned project documentation, Formal Conjectures paper, arXiv v1

3 declarations, 0 contain sorry, 0 declared as axioms

The AnswerLinter

The AnswerLinter is a linter to aid with using answer(sorry) correctly.

Imports (3)

Imported by 2 files

def AnswerLinter.contains_early_args Helper to check for arguments (h : True) line 40 source
Source comment
Helper to check for arguments (h : True)

standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses: Lean.Syntax, Lean.Elab.Command.CommandElabM, Bool
Proof uses: GetElem.getElem, Nat, True, OfNat.ofNat, True.intro, ite, Eq, bne, Lean.SyntaxNodeKind, Lean.Syntax.getKind, Lean.Name.mkStr4, Bool.true, Pure.pure, Lean.Elab.Command.Context, StateRefT', IO.RealWorld, Lean.Elab.Command.State, EIO, Lean.Exception, Bool.false and 4 more
10 instances, coercions and auxiliary constants left out.
```
def contains_early_args (stx : Syntax) : CommandElabM Bool := do
…
```
def AnswerLinter.stars_with_answer_sorry_iff Helper to check for answer(sorry) ↔ line 48 source
Source comment
Helper to check for answer(sorry) ↔ ...

standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses: Lean.Syntax, Lean.Elab.Command.CommandElabM, Bool
Proof uses: GetElem.getElem, Nat, True, OfNat.ofNat, True.intro, ite, Eq, bne, Lean.SyntaxNodeKind, Lean.Syntax.getKind, Lean.Name.mkStr4, Bool.true, Pure.pure, Lean.Elab.Command.Context, StateRefT', IO.RealWorld, Lean.Elab.Command.State, EIO, Lean.Exception, Bool.false and 5 more
10 instances, coercions and auxiliary constants left out.
```
def stars_with_answer_sorry_iff (stx : Syntax) : CommandElabM Bool := do
…
```
def AnswerLinter.answerLinter The actual linter object line 63 source
Source documentation
The actual linter object

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, Unit, Lean.Elab.Command.CommandElabM, Pure.pure, Lean.Elab.Command.Context, StateRefT', IO.RealWorld, Lean.Elab.Command.State, EIO, Lean.Exception, Unit.unit, ite, Eq, Bool, BEq.beq, Lean.SyntaxNodeKind, Lean.Syntax.getKind, Lean.Name.mkStr4 and 14 more
13 instances, coercions and auxiliary constants left out.
```
def answerLinter : Linter where
…
```