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Re: Syntactic sugar for assignment statements: one value to multiple targets?

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Date Wed, 3 Aug 2011 03:09:34 +0100
Subject Re: Syntactic sugar for assignment statements: one value to multiple targets?
From Chris Angelico <rosuav@gmail.com>
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On Wed, Aug 3, 2011 at 2:45 AM, gc <gc1223@gmail.com> wrote:
> Anyway, I frequently need to initialize several variables to the same
> value, as I'm sure many do. Sometimes the value is a constant, often
> zero; sometimes it's more particular, such as defaultdict(list). I use
> dict() below.

If it's an immutable value (such as a constant integer), you can use
syntax similar to C's chained assignment:

a=b=c=0

If you do this with dict(), though, it'll assign the same dictionary
to each of them - not much use.

> # Option 3 (multiple target list: this seems the most Pythonic, and is
> normally what I use)
> # Concise, separates variables from assignments, but somewhat
> annoying; have to change individually and track numbers on both sides.
>
> a,b,c,d,e = dict(),dict(),dict(),dict(),dict()

I think this is probably the best option, although I would be inclined
to use dictionary-literal syntax:
a,b,c,d,e = {},{},{},{},{}

It might be possible to do something weird with map(), but I think
it'll end up cleaner to do it this way.

Chris Angelico

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Thread

Syntactic sugar for assignment statements: one value to multiple targets? gc <gc1223@gmail.com> - 2011-08-02 18:45 -0700
  Re: Syntactic sugar for assignment statements: one value to multiple targets? Chris Angelico <rosuav@gmail.com> - 2011-08-03 03:09 +0100
  Re: Syntactic sugar for assignment statements: one value to multiple targets? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-08-03 18:25 +1000
    Re: Syntactic sugar for assignment statements: one value to multiple targets? Tim Chase <python.list@tim.thechases.com> - 2011-08-03 06:15 -0500
    Re: Syntactic sugar for assignment statements: one value to multiple targets? Tim Chase <python.list@tim.thechases.com> - 2011-08-03 06:25 -0500
      Re: Syntactic sugar for assignment statements: one value to multiple targets? gc <gc1223@gmail.com> - 2011-08-16 12:50 -0700
  Re: Syntactic sugar for assignment statements: one value to multiple targets? Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2011-08-03 20:29 +1200
  Re: Syntactic sugar for assignment statements: one value to multiple targets? "Martin P. Hellwig" <martin.hellwig@gmail.com> - 2011-08-16 21:39 +0100
    Re: Syntactic sugar for assignment statements: one value to multiple targets? gc <gc1223@gmail.com> - 2011-08-16 17:14 -0700
      Re: Syntactic sugar for assignment statements: one value to multiple targets? MRAB <python@mrabarnett.plus.com> - 2011-08-17 03:11 +0100
      Re: Syntactic sugar for assignment statements: one value to multiple targets? Chris Angelico <rosuav@gmail.com> - 2011-08-17 08:13 +0100
        Re: Syntactic sugar for assignment statements: one value to multiple targets? gc <gc1223@gmail.com> - 2011-08-17 02:26 -0700
          Re: Syntactic sugar for assignment statements: one value to multiple targets? Chris Angelico <rosuav@gmail.com> - 2011-08-17 10:45 +0100
            Re: Syntactic sugar for assignment statements: one value to multiple targets? gc <gc1223@gmail.com> - 2011-08-17 03:33 -0700
          Re: Syntactic sugar for assignment statements: one value to multiple targets? Terry Reedy <tjreedy@udel.edu> - 2011-08-17 12:12 -0400
          Re: Syntactic sugar for assignment statements: one value to multiple targets? MRAB <python@mrabarnett.plus.com> - 2011-08-17 17:55 +0100
          Re: Syntactic sugar for assignment statements: one value to multiple targets? Chris Angelico <rosuav@gmail.com> - 2011-08-17 18:25 +0100
          Re: Syntactic sugar for assignment statements: one value to multiple targets? "OKB (not okblacke)" <brenNOSPAMbarn@NObrenSPAMbarn.net> - 2011-08-17 19:13 +0000
      Re: Syntactic sugar for assignment statements: one value to multiple targets? Zero Piraeus <schesis@gmail.com> - 2011-08-17 16:07 -0400
  Re: Syntactic sugar for assignment statements: one value to multiple targets? Ethan Furman <ethan@stoneleaf.us> - 2011-08-17 12:52 -0700
  Re: Syntactic sugar for assignment statements: one value to multiple targets? John Pinner <funthyme@gmail.com> - 2011-08-18 02:26 -0700
  Re: Syntactic sugar for assignment statements: one value to multiple targets? Roy Smith <roy@panix.com> - 2011-08-18 09:13 -0400

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