Explanation of this Python language feature? [x for x in x for x in x] (to flatten a nested list)

Mark Lawrence breamoreboy at yahoo.co.uk
Sat Mar 22 18:57:21 CET 2014


On 22/03/2014 09:09, Ian Kelly wrote:
> On Fri, Mar 21, 2014 at 8:06 PM, Rustom Mody <rustompmody at gmail.com> wrote:
>> Two: A comprehension variable is not bound but reassigned across the
>> comprehension. This problem remains in python3 and causes weird behavior when
>> lambdas are put in a comprehension
>
> Because Python as a language only has the concept of assignment, not
> binding.  I think it would be weird and confusing if variables worked
> this way in comprehensions and nowhere else.
>

My understanding has always been that an expression of the rhs is bound 
to a name of the lhs.  So is my understanding wrong, or is the above 
wrong, or are we talking at cross purposes, or what?

-- 
My fellow Pythonistas, ask not what our language can do for you, ask 
what you can do for our language.

Mark Lawrence

---
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com





More information about the Python-list mailing list