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[Python-Dev] Adding a conditional expression in Py3.0

Terry Reedy tjreedy at udel.edu
Wed Sep 21 03:21:26 CEST 2005 
"John J Lee" <jjl at pobox.com> wrote in message 
news:Pine.LNX.4.58.0509202331440.6289 at alice...
> The stricter form where you don't allow 'elif' will get used in more
> restricted circumstances, so gives less encouragement for widespread 
> abuse
> of conditional expressions by people who don't like whitespace-based
> syntax.

I think 'abusiveness' is somewhat in the eye of the beholder here.  In any 
case, without 'elif', one could still chain expressions by writing

x = (if a then b else
      (if c then d else
                      e))

which is even more Lispish.  I personally think one () is enough and prefer

x = (if   a then b
       elif c then d
                else e)

which is similar to how I wrote such things in C.  Elif has the same 
justification here as with the statement form, where it is also unnecessary 
but saves nesting levels.

Terry J. Reedy
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