Path: utzoo!attcan!uunet!cs.utexas.edu!sdd.hp.com!hplabs!hplabsz!mayer
From: mayer@hplabsz.HPL.HP.COM (Niels Mayer)
Newsgroups: comp.lang.scheme
Subject: Re: Scheme implementation strategies (was: Free Macintosh Scheme)
Message-ID: <5613@hplabsz.HPL.HP.COM>
Date: 17 Jul 90 22:53:40 GMT
References: <601@argosy.UUCP> <5598@hplabsz.HPL.HP.COM> <1436@tub.UUCP>
Reply-To: mayer@hplabs.hp.com (Niels Mayer)
Organization: Hewlett-Packard Labs, Software & Systems Lab, Palo Alto, CA.
Lines: 24
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In article <1436@tub.UUCP> net@tub.UUCP (Oliver Laumann) writes:
>In a Scheme implementation (written in C or a similar language) that
>does NOT compile the source code to some form of "virtual machine" code
>and then run a virtual machine to execute it, it is impossible to
>implement call/cc without assembly language coding.
>
>As far as I know, Elk is the only Scheme implementation with this
>property, i.e. it directly interprets the source code AND supports
>call/cc (this is due to the fact that it was written to be used
>as a general extension language); thus Elk needs assembly language
>coding (a few lines actually).

What about xscheme?? 

It seems to run a byte compiler, yet it requires no assembly language.

Does xscheme support call/cc correctly?

-------------------------------------------------------------------------------
	    Niels Mayer -- hplabs!mayer -- mayer@hplabs.hp.com
		  Human-Computer Interaction Department
		       Hewlett-Packard Laboratories
			      Palo Alto, CA.
				   *