Arthur A. Gleckler scripsit:

> Here's one: representing environments with scoping.

You are very elliptical, but I take this to be handled by making sure
that the new scope is preferred to the old when merging, which argument
order can arrange.  The only case where you need a merge proc is when
it's data-dependent which value is to be preserved.

--
John Cowan          http://www.ccil.org/~cowan        xxxxxx@ccil.org
Police in many lands are now complaining that local arrestees are insisting
on having their Miranda rights read to them, just like perps in American TV
cop shows.  When it's explained to them that they are in a different country,
where those rights do not exist, they become outraged.  --Neal Stephenson