PEP 308: Pep Update

[James J. Besemer]

Andrew Dalke wrote:
> James J. Besemer:
> 
>>Furthermore, (although I know you'll disagree) I'll point out that your
>>general complaint here also constitutes an argument for going with the
>>operator based alternative,
>>
>>a ? b : c
>>
>>as it couldn't possibly be confused with if/else statements.

Further evidence that I simply thought you did not like the other alternative.

> True, but it doesn't stand out as much.  

That IMHO can be greatly improved by a different style (which I mentioned 
earlier):

     a = (
         #  The value can be cached or in the database

         ( is_cached
	    ? self._get_cache[ name ]
             : self.connection.fetch( name )),  # database already open

        # The ownership is stored in the database (if the
        # name starts with "DB") or from the web service

        ( x.startswith( "DB" )
            ? self.connection.get_owner( name )
            : self.webservice.get_owner_by_name( name )))


> The use of ?: seems  more appropriate for smaller terms, 
 > and if/else for larger ones.

If adopting both forms was a possibility, we'd have that luxury.

Personally, I rather think that ?: fits most naturally with expressions and 
keywords fits most naturally with statements.  Certainly, this reflects my 
decades of C background.  But more than that, I think there's a natural 
association in that expression operators tend to be punctuation based, while 
statements virtually always are associated with keywords (all but assignment).

>I just wish you'd be willing to be more flexible about other people's
> opinion about style.
> 
> 
> I have at several times agreed that a given expression, when written
> with a ternary if/else expression,  is more readable.  My opinion though
> is that the overall readability/etc. suffers.  I don't know why I need to
> be any more flexible than I have been, 

There's no need.  I was making a "wish".  Unexpectedly, it seems to have come 
true.

> nor why I couldn't respond that you too need to be more flexible.

I suppose that's fair.

 > In any case, I think this will be my last post on this thread, since I am
 > sure I'm tapped out on it, if not idea-wise then at least emotionally
 > drained.

I do agree we covered all the bases.

And I had better get my butt out shopping for some Valentine gifts or else 
I'll be "emotionally drained" by my wife.

Regards

--jb

-- 
James J. Besemer		503-280-0838 voice
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