English
If P is a property of ring maps from R to S, and hP and hP' guarantee compatibility with localization to R→S, then f lies in OfLocalizationSpan P.
Русский
Если P описывает свойство отображений R→S и есть совместимость локализации через hP и hP', то f удовлетворяет OfLocalizationSpan P.
LaTeX
$$$\\text{OfLocalizationSpanTarget }P \\wedge \\text{IsLocalization compatibility} \\Rightarrow P f$$$
Lean4
theorem HoldsForLocalizationAway (hP : RingHom.PropertyIsLocal @P) (hPi : ContainsIdentities P) :
RingHom.HoldsForLocalizationAway @P := by
introv R _
have : algebraMap R S = (algebraMap R S).comp (RingHom.id R) := by simp
rw [this]
apply hP.StableUnderCompositionWithLocalizationAwayTarget S r
apply hPi