3 timesRepeat: [Warning signal].
10 factorial

Select the above in a workspace, select "debug it" then, in the
debugger, click the "Over" button just once.

3 Warning pre-debuggers appear instantly and then the execution moves
to the "factorial".

Warnings have the opportunity to resume or cancel?  IOW, shouldn't it
work more like as if it were a halt?

3 timesRepeat: [ self halt ].
10 factorial