Breaking out CommandHistory

Part of the System -> MorphicExtras dependency stems from references
to CommandHistory. Now it seems that CommandHistory has almost nothing
to do with MorphicExtras. The only thing that ties it to that package
is CommandHistory class >> #resetAllHistory, which has the line

MorphExtension withAllSubclassesDo:
    [:mexc | self forgetAllGrabCommandsFrom: mexc someInstance]

So it occurs to me that CommandHistory is useful beyond the context of
a MorphicUI, and hence perhaps we can resolve this territory dispute
thusly:
* move CommandHistory to somewhere in System (System-Support, perhaps), and
* leave resetAllHistory in MorphicExtras, perhaps with
#forgetAllGrabCommandsFrom:.

This doesn't fully resolve the issue, because SmalltalkImage >>
#zapAllOtherProjects calls #resetAllHistory (among other
dependency-on-MorphicExtras-causing actions), but does snip one more
thread.

What do you think?

frank

On 2013-05-22, at 13:46, Frank Shearar <[hidden email]> wrote:

So far it has only been used with morphs, but indeed, having system-wide undo would be great.

forgetAllGrabCommands is a more recent addition, added 2 years after the general undo support it seems. There should be a better way to integrate it than the direct dependency.

- Bert -