Suggestion for fixing %(foo)s (Re: [Python-Dev] PEP 292-related: why string substitution is not the same operation as data formatting)

[Guido van Rossum]

> > > Guido, can you please, for our enlightenment, tell us what are the
> > > reasons you feel %(foo)s was a mistake?
> > 
> > Because of the trailing 's'.  It's very easy to leave it out by
> > mistake
> 
> How about introducing a new format
> 
>   %{foo}
> 
> which is defined to be the same as %(foo)s.

Maybe too subtle (you'd really have to explain the history to make
people understand why there's both %() and %()), and doesn't solve the
compile time / run time issue IMO.

--Guido van Rossum (home page: http://www.python.org/~guido/)