From: William.H.Duquette at jpl.nasa.gov (William H. Duquette)
Date: Wed, 28 Apr 1999 14:58:13 GMT
Subject: try vs. has_key()
References: <aahzFAM4oJ.M7M@netcom.com> <yWOT2.6007$8m5.9320@newsr1.twcny.rr.com> <Pine.SUN.3.95-heb-2.07.990423140345.21577A-100000@sunset.ma.huji.ac.il>
Message-ID: <37247ea3.494305@news.jpl.nasa.gov>
X-UID: 312                                                  

On Fri, 23 Apr 1999 14:13:59 +0300, Moshe Zadka
<moshez at math.huji.ac.il> wrote:


>d={}
>for word in words:
>	first_two=word[:2]
>	d[first_two]=d.get(first_two, []).append(word)
>
>Unfortunately, few people seem to know about the ``get'' method, which
>is really good. 

This doesn't seem to work.  For example, here's a python
interpreter session:

>>> d = {}
>>> a = 'Foo'
>>> d[a] = d.get(a, []).append('Bar')
>>> d
{'Foo': None}
>>>

I'd have expected to see {'Foo': 'Bar'}, but that's not what I get.

I'm using Python 1.5.2, by the way.

Will Duquette
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