[plt-scheme] Version incompatibilities in PLaneT packages

From: Eli Barzilay (eli at barzilay.org)
Date: Tue Mar 21 18:24:33 EST 2006

On Mar 21, Jacob Matthews wrote:
> The problem with that approach is that a library might work with a
> resource that it can't have two of no matter how many different
> copies of it exist. For instance you could make a library that kept
> a flat file database somewhere; if two copies of your library are
> running at all they'll step on each other's toes, and there's
> nothing planet can do about that no matter what it does short of
> creating two completely separate sandboxes. Extra copies of the
> library won't help.

But that would be a problem in any case -- since you can run to
mzscheme processes etc.  You can also get two instances if you require
a module at different phases, or from different namespaces, so it
seems like a single-use module is an exception.

> Programs like that were actually the very first motivating example
> for adding this check at all.

          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                  http://www.barzilay.org/                 Maze is Life!

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