Perlish dictionary behavior

[Fred Allen]

Mr. Brewer:

I fruitlessly tried your "thing counter", as you can see below.
[color=blue][color=green][color=darkred]
>>> class AllThingsStartA tZero(dict):[/color][/color][/color]
.... def getitem (self, key):
.... return dict.get(self, key, 0)
....[color=blue][color=green][color=darkred]
>>> thingCounts = AllThingsStartA tZero()
>>> for thing in ('a','b','c','d ','a'):[/color][/color][/color]
.... thingCounts[thing] += 1
....
Traceback (most recent call last):
File "<interacti ve input>", line 2, in ?
KeyError: 'a'[color=blue][color=green][color=darkred]
>>> thingCounts[/color][/color][/color]
{}

Reason tells me it should work for me using...

PythonWin 2.3.4 (#53, May 25 2004, 21:17:02) [MSC v.1200 32 bit
(Intel)] on win32.

....as it did for you. The runtime interpreter, however, says
otherwise. Can you see what I've done wrong...I can't?

With thanks in advance, I am,

Respectfully yours,

Fred Allen

[Chris Liechti]

Re: Perlish dictionary behavior

fallen@leveltwo .com (Fred Allen) wrote in
news:72976037.0 406081556.6d4dd 9e7@posting.goo gle.com:
[color=blue]
> Mr. Brewer:
>
> I fruitlessly tried your "thing counter", as you can see below.
>[color=green][color=darkred]
>>>> class AllThingsStartA tZero(dict):[/color][/color]
> ... def getitem (self, key):[/color]

it's __getitem__ note the underlines.
[color=blue]
> ... return dict.get(self, key, 0)
> ...[color=green][color=darkred]
>>>> thingCounts = AllThingsStartA tZero()
>>>> for thing in ('a','b','c','d ','a'):[/color][/color]
> ... thingCounts[thing] += 1
> ...
> Traceback (most recent call last):
> File "<interacti ve input>", line 2, in ?
> KeyError: 'a'[color=green][color=darkred]
>>>> thingCounts[/color][/color]
> {}
>
> Reason tells me it should work for me using...
>
> PythonWin 2.3.4 (#53, May 25 2004, 21:17:02) [MSC v.1200 32 bit
> (Intel)] on win32.
>
> ...as it did for you. The runtime interpreter, however, says
> otherwise. Can you see what I've done wrong...I can't?
>
> With thanks in advance, I am,
>
> Respectfully yours,
>
> Fred Allen[/color]