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Re: Lishp :)


>Alan Grimes:
>I've been studying Lishp theze dayze. It seems that it has much in common with
>FORTH...

Lisp and Forth are interactive, as are Logo, Smalltalk, Basic, APL and others.
Lisp and Forth are extensible, as are Logo, Smalltalk, and very few others.
Lisp and Forth have not much more in common.

Lisp has a functionnal, prefixed syntax with variable number of args and with
parens and dots separators to delimit lists and cons' car/cdr, whereas Forth
has a minimalist procedural, postfixed syntax with fixed number of args.

Lisp interacts with the user through a conceptually simple "read-eval-print"
top-level loop (compile a "paren-nest", interpret it, and "decompile" its
functionnal result), whereas Forth relies for that on a (weird) distinction
between "compilation" and "interpretation" semantics.

Lisp requires an expensive, intensively used, memory garbage collector, and
uses a single stack with expensive dynamic binding of variables, whereas Forth
has a minimalist memory static management scheme, with two stacks and a code /
data memory handled also as a stack (last in/defined - first out/forgotten).

Have a deeper look at Lisp and Forth respective implementations, and you'll see
how different they are, that a minimal Lisp requires much more resources than a
minimal Forth, that Lisp tries its best to be bulletproof, whereas Forth lets
you all freedom, even to shoot in your foot (very easy to do it, but also to
avoid it).

CL
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