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| Date | Mon, 12 Jan 2015 12:40:13 -0800 |
| From | Ethan Furman <ethan@stoneleaf.us> |
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| Subject | Re: Namespace puzzle, list comprehension fails within class definition |
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On 01/12/2015 12:25 PM, John Ladasky wrote:
> d = {0:"a", 1:"b", 2:"c", 3:"d"}
> e = [d[x] for x in (0,2)]
>
> class Foo:
> f = {0:"a", 1:"b", 2:"c", 3:"d"}
> print(f)
> g = [f[x] for x in (0,2)]
In Foo 'f' is part of an unnamed namespace; the list comp 'g' has its own namespace, effectively making be a nonlocal;
class name lookup skips nonlocal namespaces.
Workaround: use an actual for loop.
--
~Ethan~
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Namespace puzzle, list comprehension fails within class definition John Ladasky <john_ladasky@sbcglobal.net> - 2015-01-12 12:25 -0800
Re: Namespace puzzle, list comprehension fails within class definition Ethan Furman <ethan@stoneleaf.us> - 2015-01-12 12:40 -0800
Re: Namespace puzzle, list comprehension fails within class definition John Ladasky <john_ladasky@sbcglobal.net> - 2015-01-12 12:49 -0800
Re: Namespace puzzle, list comprehension fails within class definition Steven D'Aprano <steve@pearwood.info> - 2015-01-13 04:49 +0000
Re: Namespace puzzle, list comprehension fails within class definition Ethan Furman <ethan@stoneleaf.us> - 2015-01-12 22:00 -0800
Re: Namespace puzzle, list comprehension fails within class definition John Ladasky <john_ladasky@sbcglobal.net> - 2015-01-12 12:43 -0800
Re: Namespace puzzle, list comprehension fails within class definition Chris Angelico <rosuav@gmail.com> - 2015-01-13 07:51 +1100
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