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Date: Fri, 7 Jun 2013 23:16:22 -0500
From: Tim Chase <python.list@tim.thechases.com>
To: Carlos Nepomuceno <carlosnepomuceno@outlook.com>
Subject: Re: Idiomatic Python for incrementing pairs
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References: <20130607213239.3e39a448@bigbox.christie.dr> <BLU176-W41787828AF1636314057B8D79A0@phx.gbl>
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Xref: csiph.com comp.lang.python:47365

On 2013-06-08 07:04, Carlos Nepomuceno wrote:
> alpha, beta = (1 if some_calculation(params) else 0, 1 if
> other_calculation(params) else 0)

This one sets them to absolute values, rather than the incrementing
functionality in question:

> >   alpha += temp_a
> >   beta += temp_b

The actual code in question does the initialization outside a loop:

  alphas_updated = betas_updated = 0
  for thing in bunch_of_things:
    a, b = process(thing)
    alphas_updated += a
    betas_updated += b

and it just bugs me as being a little warty for having temp
variables when Python does things like tuple-unpacking so elegantly.
That said, as mentioned in a contemporaneous reply to Jason, I haven't
found anything better that is still readable.

-tkc