Commit 2026-08-23 14:46 f2916a54
View on Github →refactor(CategoryTheory/Sites): split long file Sieves.lean (#43014) Split this file into the following pieces:
- Presieve.lean — 434 lines — Presieves, arrow families, binding, pullback and pushforward along morphisms, pullback existence, and uncurrying.
- Basic.lean — 526 lines — Core sieve theory: generation, lattice structure, arrow families, pullbacks, and pushforwards.
- Functoriality.lean — 438 lines — Pullback, pushforward, and mapping of both presieves and sieves along functors and equivalences.
- Presheaf.lean — 153 lines — The presheaf associated to a sieve and its inclusion into the Yoneda presheaf.
- Shrink.lean — 83 lines — Universe-shrunk sieve presheaves and their comparison isomorphisms.