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Date: Wed, 02 Apr 2014 11:15:13 -0700
From: Ethan Furman <ethan@stoneleaf.us>
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Subject: Re: Retrieve item deep in dict tree?
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Xref: csiph.com comp.lang.python:69552

On 04/02/2014 10:58 AM, Roy Smith wrote:
>
> I have a big hairy data structure which is a tree of nested dicts.  I have
>  a sequence of strings which represents a path through the tree.  Different
>  leaves in the tree will be at different depths (which range from 1 to about
>  4 or 5 at most).  I want to get the value stored at that path.  Thus, if
>
>   keys = ['foo', 'bar', 'baz']
>
> I want to retrieve tree['foo']['bar']['baz'].
>
> Is there some idiomatic, non-cryptic way to write that as a one-liner?
>
> I'm using Python 2.7.

Can you make the top-level tree a custom dict that understands tuple keys should be drilled down?

--
~Ethan~