On Thursday 03 February 2005 12:54 am, Stewart Stremler wrote:
> begin  quoting Andrew P. Lentvorski, Jr. as of Wed, Feb 02, 2005 at 
> 10:36:05PM -0800:
> > On Feb 2, 2005, at 8:48 PM, Stewart Stremler wrote:
>
> [snip]
>
> > >Weren't the first lisp implementations built that way? Or do those
> > >count as "toy implementations" as well?
> >
> > Sure, the *first* implementations were probably built that way.
> > However, most of the various dialects by 1980 had much better
> > implementations.
>
> Naturally.  It's an obvious thing to optimize on.  And if the optimization
> is relatively transparent and doesn't change the syntax of the language,
> it's conceptually irrelevent ... everything behaves /as if/ it were all
> cons-cells.

Not really. The guys who knew what was going on were often using
that implementation detail to dig deeper into the underlying data
structure. This leads to (as you might expect) a huge number of
difficulties when the implementation is changed. 

This problem was a killer for a lot of FORTH code that 
was from a modern perspective too integrated, i.e. the 
implementation was seamlessly optimized. 

But it made a lot of sense to those who understood it 
at the time. Not really much different from the early 
LISP code.

boblq



-- 

KPLUG-List mailing list
[email protected]
http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list

Reply via email to