Marker provides a way to quickly reset the dictionary and heap to the state it was in prior to the creation of the marker.

The Code

~~~:class:marker (a-)   compiling? [ compile:lit &class:marker compile:call ]              [ fetch-next !Dictionary fetch !Heap     ] choose ;   :marker (s-) [ @Heap @Dictionary ] dip d:create , , &class:marker reclass ; ~~~

A Test Case

```:a #1 #2 #3 ; :b a + + ; :c b n:put nl ; c 'd marker :a #4 #5 #6 ; :b a + + ; :c b n:put nl ; c d c ```