Picture Object

Each backend provides an object named Picture that provides easy access to constructors. Constructors are algebra methods that produce a Picture but don't have any Drawing[A] parameter. For example, all the methods on the Shape algebra are constructors.

The Picture object allows us to write


to call the circle method on Shape.

Be aware that calling Picture.circle will create a Picture. Calling the Shape algebra directly produces a Drawing, which is usually not what we want, so Doodle adds this convenience for the API it expects you to use.