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Newsgroups: comp.lang.python
Date: Sun, 15 Jul 2012 12:47:26 -0700 (PDT)
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Subject: Re: Request for useful functions on dicts
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Xref: csiph.com comp.lang.python:25371

Thanks for the suggestions, Ian!  I implemented most of them and pushed the=
 code.

> That&#39;s because the Pythonic way is to either create a new object and
> return it, or mutate the existing object and return None.

You're saying what I was already thinking.

> In Python 2.7+, intersection and difference could be written using
> dictviews, which act like sets.

I'm debating with myself right now whether to support 2.5 and 2.6.

> def partition(f, d):

Good idea, thanks.

> issubdict could be implemented as a subset operation.  I haven&#39;t time=
d

The current implementation is a bit faster, and it's quite a bit faster on =
the common (for me) case, where one argument is much smaller than the other=
.  I wrote it that way because if m=3Dlen(first), n=3Dlen(second), the amou=
nt of work is O(min(m,n)).  Your implementation is O(m + n).  Not really a =
big deal, unless e.g. m << n.=20

--Leif