[plt-scheme] Re: to define, or to let

From: Paul Schlie (schlie at comcast.net)
Date: Mon Apr 26 22:18:23 EDT 2004

> Joe Marshall wrote in response to Bill Richter:
> ....

Rather than hashing through each point, please consider the following
observations to your various points:

- evaluation order refers to "evaluation", if the author of a macro chooses
to effectively reorder arguments prior to their evaluation, that¹s their
prerogative; however regardless of their choice, the resulting program
should be semantically (behaviorally) unambiguous, which can only be
achieved by specifying evaluation order.

- if two programs (utilizing any combination of expressions and/or macros),
are equivalent under R5RS, and not if argument order is specified; then
those same two programs are behaviorally ambiguous under R5RS, therefore
meaningless to no one's benefit; as opposed to having a well defined
meaning/behavior otherwise if evaluation order were specified.

Rather than continuing to argue about the hypothetical merits of unspecified
evaluation order, I'll abstain, and wait for someone to produce a code
fragment which benefits from it's resulting ambiguity.

(which I am confident no one will be able to produce)


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