Lean 4 style guide and Mathlib conventions. Use whenever Lean code is the subject of the work, not only when editing: (1) writing, editing, or reviewing .lean files, (2) reading Lean source to answer a user question about it, (3) planning, proposing, or naming lemmas, definitions, theorems, or tacti
Lean 4 style guide and Mathlib conventions. Use whenever Lean code is the subject of the work, not only when editing: (1) writing, editing, or reviewing .lean files, (2) reading Lean source to answer a user question about it, (3) planning, proposing, or naming lemmas, definitions, theorems, or tactics before implementation, (4) discussing Lean design decisions, refactors, API choices, or proof str