Python syntax in Lisp and Scheme

[Duane Rettig]

jhbrown at ai.mit.edu (Jeremy H. Brown) writes:

> "Terry Reedy" <tjreedy at udel.edu> writes:
> > Other Lispers posting here have gone to pains to state that Scheme is
> > not a dialect of Lisp but a separate Lisp-like language.  Could you
> > give a short listing of the current main differences (S vs. CL)?  


> I'm sure if you do some web-groveling, you can find some substantial
> comparisons of the two; I personally think they have more in common
> than not.  Here are a few of the (arguably) notable differences:

This is actually a pretty good list.  I'm not commenting on
completeness, but I do have a couple of corrections:

>                         Scheme          Common Lisp
> Philosophy              minimalism      comprehensiveness
> Namespaces              one             two (functions, variables)
> Continuations           yes             no
> Object system           no              yes
> Exceptions              no              yes
> Macro system            syntax-rules    defmacro
> Implementations         >10             ~4
===========================================^

See http://alu.cliki.net/Implementation - it lists 9 commercial
implementations, and 7 opensource implementations.  There are
probably more.

> Performance             "worse"         "better"
> Standards               IEEE            ANSI
> Reference name          R5RS            CLTL2
============================================^

No, CLtL2 is definitely _not_ a reference for ANSI Common Lisp.
It was a snapshot taken in the middle of the ANSI process, and
is out of date in several areas.  References which are much closer
to the ANSI spec can be found online at 

http://www.franz.com/support/documentation/6.2/ansicl/ansicl.htm

or

http://www.lispworks.com/reference/HyperSpec/Front/index.htm

> Reference length        50pp            1029pp
> Standard libraries      "few"           "more"
> Support Community       Academic        Applications writers
> 
> The Scheme community has the SRFI process for developing additional
> almost-standards.  I don't know if the CL community has something
> equivalent; I don't think they did a year ago.

There are many grassroots defacto standards efforts to extend CL in
several areas.  Some of these are listed here:

http://alu.cliki.net/Standard

> > If I were to decide to expand my knowledge be exploring the current
> > versions of one(I've read the original SICP and LISP books), on what
> > basis might I make a choice?
> 
> Try them both, see which one works for you in what you're doing.

Agreed, but of course, I'd recommend CL :-)

-- 
Duane Rettig    duane at franz.com    Franz Inc.  http://www.franz.com/
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