On 22 Nov 2005 11:18:19 -0800, "Kay Schluehr" <[EMAIL PROTECTED]> wrote:
>Bengt Richter wrote:
>> On Mon, 21 Nov 2005 01:27:22 +0100, Christoph Zwerschke <[EMAIL PROTECTED]>
>> wrote:
>
>> Note that is isn't hard to snap a few pieces together to make an ordered
>> dict to your own specs. But IMO it belongs in pyPI or such, not in the system
>> library. At least until it gets a lot of mileage -- and MMV ;-)
>
>It's also not very hard to write a hex2ascii converter. That's the
>reason why 20 incompatible versions of it ( coded in C ) exists in my
>department ;)
Bicycle shed effect, I guess ;-)
>
>Kay
>
>PS. Here is some attempt of my own to implement an odict, following the
>discussion here.
>The implementation highlights just the model and is incomplete:
>
This is essentially the tack I took in modifying odict.py, except I
added optional caching of sorted items, and other minor differences.
>class odict(dict):
> def __init__(self, create_order = True):
> dict.__init__(self)
> self.create_order = create_order
> self.__cnt = 0
>
> def __setitem__(self, key, value):
> val = dict.get(self,key)
> if val and self.create_order:
> dict.__setitem__(self, key, (val[0], value))
> else:
> self.__cnt+=1
> dict.__setitem__(self, key, (self.__cnt, value))
>
> def __getitem__(self, key):
> return dict.__getitem__(self, key)[1]
>
> def values(self):
> return list(zip(*sorted(dict.values(self)))[1])
maybe more directly
return [v for i,v in sorted(dict.values(self))]
>
> def keys(self):
> ks = [(dict.get(self,k)[0],k) for k in dict.keys(self)]
> return list(zip(*sorted(ks))[1])
or (untested)
def keys(self):
return [k for k,v in sorted(dict.items(self),
key=operator.itemgetter(1))]
def items(self):
return [(k,v[1]) for k,v in sorted(dict.items(self),
key=operator.itemgetter(1))]
>
>>>> od = odict()
>>>> od["a"] = 0
>>>> od["b"] = 8
>>>> od.keys()
>["a", "b"]
>
>>>> od = odict(create_order = False)
>>>> od["a"] = 1
>>>> od["b"] = 2
>>>> od["a"] = 3
>>>> od.keys()
>["b", "a"]
>
Regards,
Bengt Richter
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