Lets.Lens: Types for setP and getP incorrect?

[endgame]

From here:

setP :: Prism s t a b -> s -> Either t a
getP :: Prism s t a b -> b -> t

This seems backwards.

[endgame]

Further, the first function should probably have type Prism s s a a -> s -> Either s a (no type-changing) and the second should probably have type Prism s t a b -> s -> b -> t (needs a structure to set).