enum WithFilter[t: Type, a: Type]
case WithFilter(a -> Bool, t)
A view for ForEach instance t that filters out elements that don't match the predicate.
ForEach
t
instance ForEach[WithFilter[t, a]] with ForEach[t] where ForEach.Elm[t] ~ a
type Elm = a
type Aef = Aef[t]