[plt-scheme] Serializable continuations?

From: Richard Cobbe (cobbe at ccs.neu.edu)
Date: Fri Feb 10 06:42:33 EST 2006

On Thu, Feb 09, 2006 at 09:08:40PM -0800, Jim Blandy wrote:
> (I like to read papers Matthias has contributed to just for the
> notation.  One taught me about contexts, and this one is the first
> time I've seen overbars used like ... in syntax-rules.)

In the interests of giving credit where credit is due, the overbar
notation isn't really a PLT idea.  I'm not sure where it originated; I
first saw it in Igarashi, Pierce, and Wadler's Featherweight Java paper
(TOPLAS, 2001).  

Of course, we in PLT have modified the notation slightly for sequences
of multiple kinds of elements.  In the web continuation paper, see the
letrec production in figure 3: Pettyjohn et al. write

       (letrec ([sigma v]) e)

whereas Igarashi et al would have written

                  _____ _
        (letrec ([sigma v]) e)

It's a subtle difference, but we tend to think that our way scales up
better to more complex sequences.  (Not coincidentally, it's also more
consistent with the use of ellipses in syntax-rules and syntax-case.)


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