[Python-Dev] Add a "transformdict" to collections

[Ethan Furman]

On 09/11/2013 06:58 AM, Victor Stinner wrote:
>
> The os.environ mapping uses a subclass of MutableMapping which
> accepts 4 functions: encoder/decoder for the key and encoder/decoder
> for the value. Such type is even more generic. transformdict cannot
> replace os._Environ.

True, it's more generic -- but is it used more often?  Or often enough to have those four functions be part of 
transformdict instead of just the one encodekey function?  (I mean the idea of os._Environ, not that specific 
implementation.)

Personally, I wouldn't mind having all four; for one thing, the name 'transformdict' would then be entirely appropriate.  ;)

--
~Ethan~