For review: PEP 308 - If-then-else expression

[Carlos Ribeiro]

On Saturday 08 February 2003 02:51 pm, Aahz wrote:
> In article <yu998ywqdevm.fsf at europa.research.att.com>,
>
> Andrew Koenig  <ark at research.att.com> wrote:
> >The real question, then, is how much stylistic diversity the Python
> >community wants to allow.
>
> Right.  In general, Python has focused on mechanisms for reducing
> stylistic diversity, because that makes programs easier to read.

One more reason to support conditional expressions, because it will allow a 
*single way to do it*, instead of every person coming up with a different 
hack to achieve the same effect.

Today, those who want to write a simple conditional expression have three 
choices:

1) using if statements, enclosed or not in a helper function;

2) using the 'a and b or c' hack, which abuses the semantics of logical 
expression evaluation to give the desired result;

3) using the indexed tuple/list technique, which is fine for some problems, 
but mistake-prone because it forces the programmer to reverse the order of 
the 'true' and 'false' arguments (or to reverse the test condition, whatever 
you like more).

Now, having *three* different idioms is better than having a single one?


Carlos Ribeiro
cribeiro at mail.inet.com.br