Re: Bitten by my C/Java experience

From	Andrew Cooper <amc96@cam.ac.uk>
Newsgroups	comp.lang.python
Subject	Re: Bitten by my C/Java experience
Date	2015-05-04 21:57 +0100
Organization	Student-Run Computing Facility (SRCF)
Message-ID	<mi8mf6$k1$1@flame.srcf.net> (permalink)
References	<87r3qwid3u.fsf@Equus.decebal.nl> <mailman.97.1430761463.12865.python-list@python.org>

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On 04/05/2015 18:43, Ian Kelly wrote:
> 
> Some other gotchas that aren't necessarily related to C/Java but can
> be surprising nonetheless:
> 
> *    () is a zero-element tuple, and (a, b) is a two-element tuple,
> but (a) is not a one-element tuple. Tuples are created by commas, not
> parentheses, so use (a,) instead.

* {} is an empty set(), not dict().

Particularly subtle when combined with **kwargs

$ python3
Python 3.4.0 (default, Apr 11 2014, 13:05:11)
[GCC 4.8.2] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> def foo(**kwargs):
...   return { (k, kwargs[k]) for k in kwargs }
...
>>> foo()
set()
>>> foo(a=1)
{('a', 1)}
>>>

~Andrew

Thread

Bitten by my C/Java experience Cecil Westerhof <Cecil@decebal.nl> - 2015-05-04 17:20 +0200
  Re: Bitten by my C/Java experience Tobiah <toby@tobiah.org> - 2015-05-04 10:18 -0700
  Re: Bitten by my C/Java experience Irmen de Jong <irmen.NOSPAM@xs4all.nl> - 2015-05-04 19:32 +0200
    Re: Bitten by my C/Java experience Chris Angelico <rosuav@gmail.com> - 2015-05-05 03:40 +1000
      Re: Bitten by my C/Java experience albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-08 10:47 +0000
        Re: Bitten by my C/Java experience Chris Angelico <rosuav@gmail.com> - 2015-05-08 21:32 +1000
  Re: Bitten by my C/Java experience Ian Kelly <ian.g.kelly@gmail.com> - 2015-05-04 11:43 -0600
    Re: Bitten by my C/Java experience Andrew Cooper <amc96@cam.ac.uk> - 2015-05-04 21:57 +0100
      Re: Bitten by my C/Java experience random832@fastmail.us - 2015-05-04 17:16 -0400
      Re: Bitten by my C/Java experience Tim Chase <python.list@tim.thechases.com> - 2015-05-04 16:26 -0500
  Re: Bitten by my C/Java experience Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-05-04 18:59 +0100
  Re: Bitten by my C/Java experience Ian Kelly <ian.g.kelly@gmail.com> - 2015-05-04 13:39 -0600
    Re: Bitten by my C/Java experience Cecil Westerhof <Cecil@decebal.nl> - 2015-05-04 22:28 +0200
      Re: Bitten by my C/Java experience Dave Angel <davea@davea.name> - 2015-05-04 19:17 -0400
  Re: Bitten by my C/Java experience Terry Reedy <tjreedy@udel.edu> - 2015-05-04 16:06 -0400
  Re: Bitten by my C/Java experience BartC <bc@freeuk.com> - 2015-05-04 23:02 +0100
    Re: Bitten by my C/Java experience Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-05 18:19 +1000
      Re: Bitten by my C/Java experience BartC <bc@freeuk.com> - 2015-05-05 14:20 +0100
        Re: Bitten by my C/Java experience Rustom Mody <rustompmody@gmail.com> - 2015-05-05 09:24 -0700
          Re: Bitten by my C/Java experience Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2015-05-06 14:38 +0200
            Re: Bitten by my C/Java experience Rustom Mody <rustompmody@gmail.com> - 2015-05-06 06:03 -0700
        Re: Bitten by my C/Java experience Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2015-05-06 23:19 +1200
          Re: Bitten by my C/Java experience BartC <bc@freeuk.com> - 2015-05-06 13:40 +0100
            Re: Bitten by my C/Java experience Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-07 02:03 +1000
              Re: Bitten by my C/Java experience Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-05-06 21:13 +0100
      Re: Bitten by my C/Java experience Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2015-05-06 23:15 +1200
    Re: Bitten by my C/Java experience random832@fastmail.us - 2015-05-06 09:11 -0400
    Re: Bitten by my C/Java experience Chris Angelico <rosuav@gmail.com> - 2015-05-06 23:16 +1000

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