[plt-scheme] Lazy evaluation and tail calls

From: Marco Morazan (morazanm at gmail.com)
Date: Mon Feb 9 12:55:22 EST 2009

On Mon, Feb 9, 2009 at 4:38 AM, James Coglan <jcoglan at googlemail.com> wrote:
>> James, just for the record from a semanticist: the terms 'applicative
>> order' and 'normal order' make NO SENSE whatsoever in the world of PLs.
>> Period. -- Matthias
> Could you elaborate? These are terms I picked up learning Scheme from SICP
> but have also seen any number of confusing descriptions of various calling
> semantics.

SICP is not the best source to learn about the implementation of
programming languages. If you take a look at modern PLs textbooks
like, for example, EOPL you will discover that the terms applicative
order and normal order are not used. SICP is guiding you in the wrong
direction in this case. It really is all about parameter passing
variations as Matthias has pointed out to you.




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