Re: Trees

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From	Ian Kelly <ian.g.kelly@gmail.com>
Date	Wed, 21 Jan 2015 23:56:03 -0700
Subject	Re: Trees
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On Wed, Jan 21, 2015 at 10:20 PM, Rustom Mody <rustompmody@gmail.com> wrote:
> On Thursday, January 22, 2015 at 4:25:03 AM UTC+5:30, Ian wrote:
>> On Tue, Jan 20, 2015 at 6:23 PM, Rustom Mody wrote:
>> > The Haskell is bullseye¹ in capturing the essense of a tree because
>> > conceptually a tree of type t is recursive in the sense that it can contain
>> > 2 subtrees -- (B x lst rst) -- or its a base case -- L x.
>>
>> How do you create a tree containing an even number of elements under
>> this constraint?
>
> Not sure what you are asking...
>
> [And a text only group makes discussing pictur-esque things hard]
> What do you mean by 'element'?
> Leaf? Internal? Either?

By "element" I mean an individual datum contained in the tree.
Likewise the elements of a list are its contents.

Since each element is associated with a node, the question could
equally be phrased as "How do you create a tree containing an even
number of elements under this constraint?" The point I was driving at
is that the definition is incomplete -- in addition to being an
internal node or a leaf, a tree can also be empty. In fact I would
suggest that an empty tree should be the real base case, since what is
a leaf node but a node where both of its children are empty trees?

Thread

Re: Trees Terry Reedy <tjreedy@udel.edu> - 2015-01-20 01:08 -0500
  Re: Trees Marko Rauhamaa <marko@pacujo.net> - 2015-01-20 11:45 +0200
    Re: Trees Paul Rubin <no.email@nospam.invalid> - 2015-01-20 10:14 -0800
      Re: Trees Marko Rauhamaa <marko@pacujo.net> - 2015-01-20 22:26 +0200
    Re: Trees Stephen Hansen <me+python@ixokai.io> - 2015-01-20 23:56 -0800
      Re: Trees Marko Rauhamaa <marko@pacujo.net> - 2015-01-21 10:35 +0200
      Re: Trees Rustom Mody <rustompmody@gmail.com> - 2015-01-21 04:09 -0800
        Re: Trees Chris Angelico <rosuav@gmail.com> - 2015-01-21 23:35 +1100
          Re: Trees Rustom Mody <rustompmody@gmail.com> - 2015-01-21 07:24 -0800
        Re: Trees Tim Chase <python.list@tim.thechases.com> - 2015-01-21 06:55 -0600
        Re: Trees Chris Angelico <rosuav@gmail.com> - 2015-01-22 00:01 +1100
        Re: Trees Tim Chase <python.list@tim.thechases.com> - 2015-01-21 08:26 -0600
        Re: Trees Chris Angelico <rosuav@gmail.com> - 2015-01-22 01:31 +1100
        Re: Trees Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-01-22 01:47 +1100
          Re: Trees Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-21 09:15 -0700
          Re: Trees Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-21 10:27 -0700
  Re: Trees Rustom Mody <rustompmody@gmail.com> - 2015-01-20 05:33 -0800
    Re: Trees Rustom Mody <rustompmody@gmail.com> - 2015-01-20 05:51 -0800
    Re: Trees Marko Rauhamaa <marko@pacujo.net> - 2015-01-20 16:15 +0200
      Re: Trees Rustom Mody <rustompmody@gmail.com> - 2015-01-20 06:35 -0800
    Re: Trees Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-20 10:19 -0700
      Re: Trees Rustom Mody <rustompmody@gmail.com> - 2015-01-20 10:15 -0800
        Re: Trees Rustom Mody <rustompmody@gmail.com> - 2015-01-20 10:35 -0800
    Re: Trees Mario <marfig@gmail.com> - 2015-01-20 22:47 +0100
      Re: Trees Rustom Mody <rustompmody@gmail.com> - 2015-01-20 17:23 -0800
        Re: Trees Paul Rubin <no.email@nospam.invalid> - 2015-01-20 17:49 -0800
          Re: Trees Rustom Mody <rustompmody@gmail.com> - 2015-01-20 18:03 -0800
            Re: Trees Paul Rubin <no.email@nospam.invalid> - 2015-01-21 14:27 -0800
              Re: Trees Rustom Mody <rustompmody@gmail.com> - 2015-01-21 21:17 -0800
        Re: Trees Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-21 15:54 -0700
          Re: Trees Rustom Mody <rustompmody@gmail.com> - 2015-01-21 21:20 -0800
            Re: Trees Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-22 00:01 -0700
            Re: Trees Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-21 23:56 -0700
          Re: Trees Paul Rubin <no.email@nospam.invalid> - 2015-01-21 23:16 -0800
            Re: Trees Rustom Mody <rustompmody@gmail.com> - 2015-01-22 08:54 -0800
      Re: Trees Terry Reedy <tjreedy@udel.edu> - 2015-01-20 21:19 -0500
        Re: Trees Mario Figueiredo <marfig@gmail.com> - 2015-01-21 14:05 +0000

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