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

[Greg Ewing]

Has anyone considered the idea of having the string % operator
behave intelligently according to the contents of the format
string?

If it contains one or more valid %-formats, use old-style
formatting; if it contains one or more valid {}-formats,
use new-style formatting.

Ambiguous cases could arise, of course, but hopefully they
will be fairly rare, and raising an exception would point
out the problem and allow it to be fixed.

-- 
Greg