Density

trait Density[F[_], Y]

Density Comonad.

Density is Left Kan Extension where both Functors are the same.

Without any restrictions on F we can define Functor, Cobind, Comonad for Density[F]. Density is Comonad for free.

See also: https://hackage.haskell.org/package/kan-extensions/docs/Control-Comonad-Density.html

http://comonad.com/reader/2011/a-product-of-an-imperfect-union/
Companion: object

class Object

trait Matchable

class Any

Type members

Density is left Kan extension of a Functor F along itself (Lan f f).

lanToDensity(d.densityToLan) == d lanToDensity(l).densityToLan == l

The natural isomorphism between a Comonad F and the Density F.

d.lowerDensity andThen liftDensity = d