Delete from view all instances of a `Morph` class

hide_all_morphs.md

Delete all open instances of class CircleMorph:

CircleMorph allInstances do: [ :circle | circle delete ]

Or, a slightly shorter way:

CircleMorph allInstancesDo: [ :circle | circle delete ]

Notes:

• The objects will still exist in memory, but they will disappear from view.
• Any subclass of Morph class will also work here (instead of CircleMorph).