Last updated at 5:10 pm UTC on 23 February 2017
A Morph may contain other morphs. They are in a collection called 'submorphs' ("child nodes").
m := RectangleMorph new openInWorld.
The result of print-it is
i.e. no submorph.
is used to add a submorph.
Example - aRectangleMorph addMorph: anotherMorph