On 09/11/2013 02:39 PM, Tim Delaney wrote:
On 12 September 2013 02:03, Ethan Furman <firstname.lastname@example.org mailto:email@example.com> wrote:
On 09/11/2013 08:49 AM, Victor Stinner wrote: 2013/9/11 Ethan Furman <firstname.lastname@example.org <mailto:email@example.com>>: He isn't keeping the key unchanged (notice no white space in MAPPING), he's merely providing a function that will automatically strip the whitespace from key lookups. transformdict keeps the key unchanged, see the first message: >>> d = transformdict(str.lower) >>> d['Foo'] = 5 >>> d['foo'] 5 >>> d['FOO'] 5 >>> list(d) ['Foo']
That seems backwards to me. I would think that retrieving the keys from the dict would return the transformed keys (I'd call them canonical keys). That way there's no question about which key is stored - it's *always* the transformed key.
At this point there is still no question: it's the first version of the key seen. For a stupid example:
--> d = transformdict(str.lower) --> d['ThePyramid'] = 'Game Show' --> d['AtOnce'] = now() --> for k, v in d.items(): ... print(k, v)
Imagine writing a function to get that capitalization right.
In fact, I think this might get more traction if it were referred to as a canonicalising dictionary (bikeshedding, I know).
Whoa, that's way harder to spell! ;) Drop the 'ising', though, and I'm in.