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RE: Always using let*

From: Drew Adams
Subject: RE: Always using let*
Date: Sun, 14 Sep 2014 16:06:17 -0700 (PDT)

> > (The other reason is that for some Lisps the bindings of `let'
> > can be done in parallel, which can be quicker.)
    ^^^                            ^^^
> Urban legend!

Perhaps you would prefer "could" to "can"?

Lisps such as Common Lisp were specifically designed with this
parallel evaluation in mind.  The spec (and CLTL(2)) specifically
emphasizes the inherent parallelism (independence) here that
implies the *possibility* of parallel evaluation.

Whether a given Common Lisp implementation takes advantage of
this inherent parallelism is optional.  Likewise for the other
explicitly parallel constructs in CL.

For `psetf', for example, CLTL says that "the assignments of
new values are done in parallel.  More precisely, all subforms
that are to be evaluated are evaluated from left to right;
after all evaluations have been performed, all of the
assignments are performed in an unpredictable order."

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