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Date: Tue, 20 Jan 2015 09:23:50 +0000
Subject: Re: Trees
From: Nicholas Cole <nicholas.cole@gmail.com>
To: Devin Jeanpierre <jeanpierreda@gmail.com>
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On Mon, Jan 19, 2015 at 11:52 PM, Devin Jeanpierre
<jeanpierreda@gmail.com> wrote:
> On Mon, Jan 19, 2015 at 3:08 PM, Steven D'Aprano
> <steve+comp.lang.python@pearwood.info> wrote:
>> Zachary Gilmartin wrote:
>>
>>> Why aren't there trees in the python standard library?
>>
>> Possibly because they aren't needed? Under what circumstances would you use
>> a tree instead of a list or a dict or combination of both?
>>
>> That's not a rhetorical question. I am genuinely curious, what task do you
>> have that you think must be solved by a tree?
>
> In general, any time you want to maintain a sorted list or mapping,
> balanced search tree structures come in handy.
>
> Here's an example task: suppose you want to represent a calendar,
> where timeslots can be reserved for something. Calendar events are not
> allowed to intersect.

Maybe because I'm not a computer scientist, I can't immediately see
why this is a "Tree" problem and not a "Database" problem.  Genuinely
interested.