PEP-308 a "simplicity-first" alternative

[Bengt Richter]

On Wed, 12 Feb 2003 17:50:42 -0800, Erik Max Francis <max at alcyone.com> wrote:

>Bengt Richter wrote:
>
>> My fix is
>>     x and {y} or z
>> 
>> meaning y is treated as True in logical expression context, but
>> retains its value for purposes of the expression value.
>
>And, as I've pointed out through these threads, I think that cure is
>worse than the disease.
>
"That cure" hasn't been presented before AFAIK, so how can you have pointed
out anything about it before?

Unless you are looking at it through special-ternary-syntax-colored goggles,
and aren't seeing what it actually does.

It is _not_ a ternary syntax. {x} is an expression all by itself, just as [x] is,
except that all it does is guarantee that {x} will be seen as true in any logical
expression context.

It just happens to be usable to fix the hole in the old ternary idiom.
IMO it's a good substitute for using a list to guarantee
a true term, as in (x and [y] or [z])[0]

Of course, if you intensely dislike the old x and y or z idiom, making it
bullet proof will not particularly please you ;-)

OTOH, others have pointed out that the old idiom has seen considerable use
in the libraries, so maybe a 2-character bulletproofing is not such a bad idea?
Does

    x and {y} or {z}

read better as making the two choices easily identifiable?
({} is optional on the second term).

Give it another thought ;-)

Regards,
Bengt Richter