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Re: suggestions for functional style (singleton pattern?)

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Date Sat, 28 Feb 2015 22:14:11 -0700
From Michael Torrie <torriem@gmail.com>
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On 02/28/2015 09:11 PM, yves@zioup.com wrote:
> On 2015-02-28 19:19, Michael Torrie wrote:
>> You say you are trying to use a singleton pattern, but your code does
>> not appear to implement a singleton.  From what I can read of your code,
> 
> I call it a singletone because I only every create one object.
> 
> I am not trying to use a singleton, I'm trying to avoid issues created by the
> alternative ways of doing this (not having access to the variables in the repl
> etc...).
>
> There are type of problems where I don't want to bind functions to data.
>
> By the way, I have just added some more explanation in the code,
> trying to clarify the problem.

I suppose it's just a matter of style but I'd just have my utility
function return a dict of all the calculated values, rather than store
them in a utility class instance.  Then you wouldn't need an
intermediate object to hold state temporarily. The idea behind
functional programming in part is you can chain things together easily
should you need to, which your intermediate object cannot do.

But I do see kind of the pattern you are trying to employ here; I just
don't understand why it's required or what you'd use it for, given that
a function could just do all the calculations and return a list or dict
of all calculated the values.

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Thread

suggestions for functional style (singleton pattern?) yves@zioup.com - 2015-02-28 16:12 -0700
  Re: suggestions for functional style (singleton pattern?) Michael Torrie <torriem@gmail.com> - 2015-02-28 19:19 -0700
    Re: suggestions for functional style (singleton pattern?) yves@zioup.com - 2015-02-28 21:11 -0700
      Re: suggestions for functional style (singleton pattern?) Michael Torrie <torriem@gmail.com> - 2015-02-28 22:14 -0700
  Re: suggestions for functional style (singleton pattern?) Mario Figueiredo <marfig@gmail.com> - 2015-03-01 04:45 +0100
    Re: suggestions for functional style (singleton pattern?) yves@zioup.com - 2015-02-28 21:29 -0700
      Re: suggestions for functional style (singleton pattern?) Michael Torrie <torriem@gmail.com> - 2015-02-28 22:05 -0700
        Re: suggestions for functional style (singleton pattern?) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-03-02 02:55 +1100
        Re: suggestions for functional style (singleton pattern?) Fabien <fabien.maussion@gmail.com> - 2015-03-02 11:19 +0100
          Re: suggestions for functional style (singleton pattern?) Mario Figueiredo <marfig@gmail.com> - 2015-03-02 11:31 +0100
          Re: suggestions for functional style (singleton pattern?) Michael Torrie <torriem@gmail.com> - 2015-03-02 08:59 -0700
          Re: suggestions for functional style (singleton pattern?) Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-02 09:51 -0700
      Re: suggestions for functional style (singleton pattern?) Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2015-03-01 19:00 +1300
    Re: suggestions for functional style (singleton pattern?) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-03-02 02:04 +1100
      Re: suggestions for functional style (singleton pattern?) Mario Figueiredo <marfig@gmail.com> - 2015-03-01 19:20 +0100
  Re: suggestions for functional style (singleton pattern?) Paul Rubin <no.email@nospam.invalid> - 2015-02-28 22:23 -0800

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