English
If P is stable under composition with localization-away maps on the left, then Locally P is stable under such composition on the left as well.
Русский
Если P устойчива к композиции слева сAway, то Locally P устойчива слева.
LaTeX
$$$\operatorname{StableUnderCompositionWithLocalizationAwaySource}(P) \Rightarrow \operatorname{StableUnderCompositionWithLocalizationAwaySource}(\Locally P).$$$
Lean4
/-- If `P` is stable under composition with localization away maps on the left,
then so is `Locally P`. -/
theorem locally_StableUnderCompositionWithLocalizationAwaySource
(hPa : StableUnderCompositionWithLocalizationAwaySource P) :
StableUnderCompositionWithLocalizationAwaySource (Locally P) :=
by
intro R S T _ _ _ _ r _ f ⟨s, hsone, hs⟩
refine ⟨s, hsone, fun t ht ↦ ?_⟩
rw [← comp_assoc]
exact hPa _ r _ (hs t ht)