Why is there a space leak here?

Alastair David Reid reid@cs.utah.edu
05 Jun 2001 15:45:42 -0600

Mark Tullsen <tullsen@cs.yale.edu> writes:

> You have to realize that Alastair Reid is one of the truly great
> Haskell programmers on planet earth.  I'm serious.  So, when he says
> "incredibly subtle space leak" I wouldn't expect the solution to be
> simple.  As far as I can tell, your argument would also apply to
> foo2, which doesn't have a space leak.

Yeah, well, in this case this allegedly "truly great Haskell
programmer" happened to be looking at the problem the wrong way.  I
started out assuming it was a compiler or garbage collector bug and
didn't even think of trying to actually reason about the program using
the CBN calculus.


Alastair Reid

ps Tell you what, I'll make up for it by making most of the fptools/hslib
   libraries work in Hugs.  If you have read-write access to the cvs 
   repository, all you have to do (as of 20 minutes ago) is:
     cvs -d <something> checkout hugs98
     cvs -d <something> checkout fptools/hslibs
     cd hugs98/src/unix
     ./convert_hslibs ../../..   # path points to base of fptools tree
     ./configure --prefix=$HOME
     cd ..
     make install
   where <something> is whatever you normally use to get the CVS 
   repository.  Something like this

     :ext:<your username>@cvs.haskell.org:/home/cvs/root

   If you only have read access, you'll need to wait until it gets updated
   (sometime tonight) and then use


   with the password "cvs".