A modest proposition: DEFSYSTEM-DEPENDS-ON should die [was Re: What's the right way to extend ASDF with new symbols?]

[Robert Goldman]

A quick follow-up:  Perhaps this should be a lesson that trying to find
a "pure" construct for a fundamentally side-effecting operation is a Bad
Idea.

Fundamentally, extending ASDF is a global change that affects the whole
running image.  Pretending it is something else doesn't help anyone.

Now, if one wanted to have a build environment around a system build,
and change only that local environment -- so that the build of the next
ASDF system will occur in a pristine environment -- that might be possible.

If anyone wants to try to develop such a build system -- perhaps YASDF
-- more power to 'em!  But it won't be ASDF.

And maybe you should just be writing Haskell, instead ;-)

Cheers