43 lines
1.2 KiB
Plaintext
43 lines
1.2 KiB
Plaintext
From: William.H.Duquette at jpl.nasa.gov (William H. Duquette)
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Date: Wed, 28 Apr 1999 14:58:13 GMT
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Subject: try vs. has_key()
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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>
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Message-ID: <37247ea3.494305@news.jpl.nasa.gov>
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X-UID: 312
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On Fri, 23 Apr 1999 14:13:59 +0300, Moshe Zadka
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<moshez at math.huji.ac.il> wrote:
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>d={}
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>for word in words:
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> first_two=word[:2]
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> d[first_two]=d.get(first_two, []).append(word)
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>
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>Unfortunately, few people seem to know about the ``get'' method, which
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>is really good.
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This doesn't seem to work. For example, here's a python
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interpreter session:
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>>> d = {}
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>>> a = 'Foo'
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>>> d[a] = d.get(a, []).append('Bar')
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>>> d
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{'Foo': None}
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>>>
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I'd have expected to see {'Foo': 'Bar'}, but that's not what I get.
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I'm using Python 1.5.2, by the way.
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Will Duquette
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--------------------------------------------------------------------------
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Will Duquette, JPL | William.H.Duquette at jpl.nasa.gov
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But I speak only | http://eis.jpl.nasa.gov/~will (JPL Use Only)
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for myself. | It's amazing what you can do with the right tools.
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