[Python-Dev] transitioning from % to {} formatting

[Steven Bethard]

On Fri, Oct 2, 2009 at 12:43 PM, Martin Geisler <mg at lazybytes.net> wrote:
> I hate calling methods on string literals, I think it looks very odd to
> have code like this:
>
>  "Displaying {0} of {1} revisions".format(x, y)
>
> Will we be able to write this as
>
>  "Displaying {0} of {1} revisions" % (x, y)
>
> too?

I doubt it. One of the major complaints about the %-style formatting
was that the use of % produced (somewhat) unexpected errors because of
how operator precedence works::

>>> '{0}'.format(4 + 1)
'5'
>>> '%s' % 4 + 1
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: cannot concatenate 'str' and 'int' objects

Steve
-- 
Where did you get that preposterous hypothesis?
Did Steve tell you that?
        --- The Hiphopopotamus