Parenthesation in docs

Stream: general

[Yaël Dillies]

Why does docs#asymptotics.is_O_with.bound have parentheses around the filter.eventually but docs#asymptotics.is_O_with_iff doesn't?

[Gabriel Ebner]

One clear difference is → vs ↔. Presumably the pretty-printer just picks a conservative precedence on the rhs of an implication?