A Porcupine Named Edgar Allen Poke
/Selector -> Array Component
Component -> Array Selector
a -> f b
b -> f a
a -> f b
b -> g a
Hang a Fang
/// Double pass
rects.map(rect => toCoords(x).add(Inverse(toCoords(rect))))
// Single pass
rects.foldMap(rect => Min(toCoords(x).add(Inverse(toCoords(rect))))