[Python-Dev] str.format_from_mapping

[Benjamin Peterson]

2010/10/31 Glenn Linderman <v+python at g.nevcal.com>:
> On 10/31/2010 2:02 PM, Benjamin Peterson wrote:
>
> 2010/10/31 Antoine Pitrou <solipsis at pitrou.net>:
>
>> On Sun, 31 Oct 2010 16:39:44 -0400
>> Eric Smith <eric at trueblade.com> wrote:
>>
>
>>> What are your thoughts on adding a str.format_from_mapping (or similar
>>> name, maybe the suggested "format_map") to 3.2? See
>>> http://bugs.python.org/issue6081 . This method would be similar to
>>> "%(foo)s %(bar)s" % d, where d is a dict (or rather any mapping object),
>>> but of course would use str.format syntax: "{foo}
>>> {bar}".format_from_mapping(d).
>
>>
>> I must be missing something, but what's the difference with
>> XXX.format(**d)?
>
> It allows arbitrary mappings.
>
> Other than the language moratorium, why are arbitrary mappings not allowed
> for the (**d) syntax?

They are; they're just copied into a dictionary.


-- 
Regards,
Benjamin