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Re: Method chaining

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From Terry Reedy <tjreedy@udel.edu>
Subject Re: Method chaining
Date Fri, 22 Nov 2013 07:34:53 -0500
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Xref csiph.com comp.lang.python:60217

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On 11/22/2013 6:26 AM, Steven D'Aprano wrote:
> A frequently missed feature is the ability to chain method calls:
>
> x = []
> x.append(1).append(2).append(3).reverse().append(4)
> => x now equals [3, 2, 1, 4]
>
>
> This doesn't work with lists, as the methods return None

True for the 7 pure mutation methods but not for .copy, .count, .index, 
and .pop. The last both mutates and returns.

-- 
Terry Jan Reedy

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Thread

Method chaining Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-11-22 11:26 +0000
  Re: Method chaining Chris Angelico <rosuav@gmail.com> - 2013-11-22 22:44 +1100
  Re: Method chaining Peter Otten <__peter__@web.de> - 2013-11-22 13:08 +0100
    Re: Method chaining Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-11-22 14:26 +0000
      Re: Method chaining Peter Otten <__peter__@web.de> - 2013-11-22 16:20 +0100
        Re: Method chaining Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-11-22 16:26 +0000
          Re: Method chaining Wolfgang Maier <wolfgang.maier@biologie.uni-freiburg.de> - 2013-11-22 16:52 +0000
          Re: Method chaining Wolfgang Maier <wolfgang.maier@biologie.uni-freiburg.de> - 2013-11-22 17:55 +0000
      Re: Method chaining Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-11-22 16:38 +0100
      Re: Method chaining Laszlo Nagy <gandalf@shopzeus.com> - 2013-11-23 17:08 +0100
  Re: Method chaining Terry Reedy <tjreedy@udel.edu> - 2013-11-22 07:34 -0500
    Re: Method chaining Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-11-22 14:30 +0000
  Re: Method chaining Rotwang <sg552@hotmail.co.uk> - 2013-11-23 19:53 +0000
    Re: Method chaining Rotwang <sg552@hotmail.co.uk> - 2013-11-24 00:28 +0000
      Re: Method chaining Rotwang <sg552@hotmail.co.uk> - 2013-11-24 00:43 +0000
    Re: Method chaining Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-11-24 14:27 +0000
      Re: Method chaining Rotwang <sg552@hotmail.co.uk> - 2013-11-24 15:01 +0000

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