() Stefan Monnier <monnier@iro.umontreal.ca>
() Mon, 22 Jul 2013 11:24:13 -0400

   So maybe a when-let makes sense, tho I'd prefer a when-let*
   (which has also been seen under the name let-and, IIRC).

Are you willing to consider Scheme's ‘and-let*’ (SRFI 2).

IIRC i also proposed, maybe a year back, a Schemish ‘cond’
(with ‘=>’) but it was rejected.  RMS suggested instead:

 (cond VAR (CONDITION [BODY...])
           ...)

which would bind VAR to the (non-nil) value of CONDITION
such that BODY can refer to it, equivalent to:

 (let (VAR)
   (cond ((setq VAR CONDITION) [BODY...])
         ...))

I like this; it strikes me as more Lispy.  Unfortunately, i don't
remember if this "cond w/ VAR" went anywhere (so probably it didn't).

-- 
Thien-Thi Nguyen
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