Re: grab dict keys/values without iterating ?!

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Date	Wed, 11 Dec 2013 09:42:53 -0600
From	Tim Chase <python.list@tim.thechases.com>
To	Roy Smith <roy@panix.com>
Subject	Re: grab dict keys/values without iterating ?!
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On 2013-12-11 09:46, Roy Smith wrote:
> The problem is, that doesn't make a whole lot of sense in Python.
> The cited implementation uses dicts at each level.  By the time
> you've done that, you might as well just throw all the data into
> one big dict and use the full search string as the key.  It would
> be a lot less code, and probably run faster.

You're right if the search term is a whole word, a single
dict-to-result works ideally. However, the OP asked about prefixes, so
the Python implementation I provided uses a dict-of-nested-dicts which
allows any arbitrary prefix, and then iterates over only the subset of
those that match.

If you need O(length-of-prefix) iteration of all results, I believe
that's the best way algorithm to use (implementation details could
differ for a more space-efficient structure perhaps; normalization
might help reduce dict-entries).

It's a specialized use-case, and doesn't have the O(1) lookup for
exact-matches (that's just a special case of prefix=word with no
sub-iteration, so would be O(length-of-search-word)).	

-tkc

Thread

Re: grab dict keys/values without iterating ?! Tamer Higazi <tameritoke2@arcor.de> - 2013-12-11 12:07 +0200
  Re: grab dict keys/values without iterating ?! rusi <rustompmody@gmail.com> - 2013-12-11 05:31 -0800
    Re: grab dict keys/values without iterating ?! Roy Smith <roy@panix.com> - 2013-12-11 09:46 -0500
      Re: grab dict keys/values without iterating ?! rusi <rustompmody@gmail.com> - 2013-12-11 07:08 -0800
      Re: grab dict keys/values without iterating ?! Tim Chase <python.list@tim.thechases.com> - 2013-12-11 09:42 -0600
    Re: grab dict keys/values without iterating ?! Travis Griggs <travisgriggs@gmail.com> - 2013-12-11 09:19 -0800
    Re: grab dict keys/values without iterating ?! Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-12-11 18:09 +0000
  Re: grab dict keys/values without iterating ?! Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-12-11 13:44 +0000
    Re: grab dict keys/values without iterating ?! Tim Chase <python.list@tim.thechases.com> - 2013-12-11 08:30 -0600
    Re: grab dict keys/values without iterating ?! Ian Kelly <ian.g.kelly@gmail.com> - 2013-12-11 18:02 -0700
    Re: grab dict keys/values without iterating ?! Ian Kelly <ian.g.kelly@gmail.com> - 2013-12-11 18:05 -0700

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