Subject: Re: ??: using * for variable ?
From: Erik Naggum <>
Date: 1999/03/20
Newsgroups: comp.lang.lisp
Message-ID: <>

* Barry Margolin <>
| Are deep bindings every really used in serious implementations?  I've
| rarely encountered it, and I tend to think of them more as an issue for
| academic discussion of design techniques.  The benefit of deep binding is
| that stack unwinding is cheap, but at the expense of slow dynamic
| variable access, and this seems like a poor tradeoff.

  there may be a reason to use deep binding in a multiprocessing
  environment where you may have to switch contexts very often and this
  should be virtually free.  switching values of a whole bunch of bindings
  in a context switch can get expensive in shallow binding.  I don't know
  if this would actually hold true in any real system or in any real use,
  but it's worth noting that context switching is expensive, and perhaps we
  will find the best solutions in unexpected corners of the solution space.