[Python-Dev] Status regarding Old vs. Advanced String Formating

[Ned Batchelder]

On 2/24/2012 7:23 PM, Mark Lawrence wrote:
> I think this is daft because all of the code has to be supported for 
> the ten years that MVL has suggested.  I suggest a plan that says 
> something like:-
>
> Until Python 3.5 both methods of string formatting will be supported.
> In Python 3.6 the the old formating style will be deprecated.
> In Python 3.7 the old style is dead.
>
> I'm fully aware that it isn't likely to be that easy, I'm simply 
> trying to spark ideas from the core developers and users who are in a 
> far better situation to judge this situation than I am.
I don't understand why we'd even consider getting rid of old-style 
formatting.  Python does a great job keeping things working into the 
future, and there are so many features in the language and library that 
are there to keep old code working in spite of newer ways to accomplish 
the same task.  Has Python *ever* removed a feature except in X.0 
releases?  Why are we even discussing this?

Two ways to format strings is no big deal, especially considering how 
heavily used these tools are.  And btw, if you include the 
almost-never-mentioned string.Template, there are at least three ways to 
do it, maybe more.

--Ned.