[Python-Dev] Adding C ternary select (a?b:c) to Python?

[Jim Fulton]

Christopher Petrilli wrote:
> 
> The question comes from what "problem" you're trying to solve. 

It would allow you to incorporate logic into expressions. 
There are contexts where only expressions are allowed, such as:

  - lambdas

  - DTML expr attributes

in which I'd very much like to incorporate tests.

> The ?: syntax
> does not introduce any new "functionality" to the language,

Yes it does.

> nor does it
> make it capable of solving problems or requirements that it can not do
> at the current time.

Ditto.
 
> The second qustion I'd ask is, who is this aimed at?  It's certainly not
> aimed at first-time programmers, as I know from experience that the ?:
> is one of the hardest things to teach people in C (after pointers),

Hm. I can't agree.

Smalltalk, came out of an essentially CP4E effort
two decades ago at Xerox PARC.  Smalltalk *only* had conditional
expressions. The message:

  [condition] ifTrue: [do something ...]
              ifFalse: [do something else ...]

is an expression in Smalltalk.

> and
> often I leave it out of training when I did it.  It's simply a "shorthand"
> not a new functionality. 

No, it allows testing in expressions.

> If its aimed at experienced programmers, I'd
> argue that it's at best "non-pythonic" and at worst a hack, taken from
> a language in which it exposes the "macro assembler" approach.

I don't agree.

> Python is not a language that has been optimized for "minimal typing",

That's not the issue.

> it's
> much more verbose than most languages, and so that argument shouldn' be
> applied.  Perhaps it's for optimization?  That was I believe the original
> argument made for it in K&R, in that optimizers in that day were rather
> antiquated, wheras today, I believe that any C compiler would get it
> right if it were expressed in its full form. (Timbot?)
> 
> So, it comes down to a few questions for me:
> 
>         Does it solve a new problem?    No

Yes.

>         Is it pythonic?                 No

Pythonicity is relative.

>         Does it make it faster?         No

Who cares?
 
Jim

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