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Re: How to improve the readability of (any) LISP or any highlevel functi


From: P.M.Lawrence
Subject: Re: How to improve the readability of (any) LISP or any highlevel functional language to the level of FORTH ?
Date: Tue, 4 Jan 2011 06:14:49 -0800 (PST)
User-agent: G2/1.0

pineapple wrote:
> On Jan 1, 2:04 pm, girosenth <address@hidden> wrote:
>
> > Is there a postfix functional language that also gets rid of parens
> > and is not as primitive as FORTH or POSTSCRIPT ?
>
> Joy.
>
> http://en.wikipedia.org/wiki/Joy_(programming_language)

Not quite; that does use bracketing around chunks of code, as much as
anything for quoting purposes to allow lazy evaluation.

The problem with a completely postfix notation for a functional
language is that parameters are evaluated as they turn up, without
regard to the operation that needs them (as, without lookahead that
would destroy the gains from postfix notation, it isn't yet known what
will be needed). That appears to enforce strict evaluation, unless the
postfix notation is loosened with some quoting system.

However, I did some work on this myself for my Furphy project (see
http://users.beagle.com.au/peterl/furphy.html - but so far it's only a
prototype/testbed, and still quite "primitive"). I found an
indirection mechanism that gave lazy evaluation without a quoting
system, which I implemented with the complementary keywords FREEZE and
THAW. Even so, a quoting system is so convenient that I added one back
in - only, now it is a layer of syntactic sugar rather than an
alternative treatment of the source. I wanted to avoid that
alternative treatment so that inconsistencies wouldn't develop from
going in and out of postfix notation - I was even able to make keyword
naming postfix. P.M.Lawrence.


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