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Is there a reason zip() wipes out data?

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  Is there a reason zip() wipes out data? DFS <nospam@dfs.com> - 2016-05-09 00:22 -0400
    Re: Is there a reason zip() wipes out data? Dan Sommers <dan@tombstonezero.net> - 2016-05-09 04:29 +0000
    Re: Is there a reason zip() wipes out data? Paul Rubin <no.email@nospam.invalid> - 2016-05-08 23:06 -0700

#108411 — Is there a reason zip() wipes out data?

python 2.7.11 docs: "The returned list is truncated in length to the 
length of the shortest argument sequence."


a = ['who','let','the']
b = ['dogs','out?']
c = zip(a,b)

print c
[('who', 'dogs'), ('let', 'out?')]


Wouldn't it be better to return an empty element than silently kill your 
data?

[('who', 'dogs'), ('let', 'out?'), ('the', '')]




Edit: I see they addressed this in 3.5 (maybe earlier), with an option:

"itertools.zip_longest(*iterables, fillvalue=None)

Make an iterator that aggregates elements from each of the iterables. If 
the iterables are of uneven length, missing values are filled-in with 
fillvalue. Iteration continues until the longest iterable is exhausted."

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#108412

On Mon, 09 May 2016 00:22:46 -0400, DFS wrote:

> python 2.7.11 docs: "The returned list is truncated in length to the 
> length of the shortest argument sequence."
> 
> 
> a = ['who','let','the']
> b = ['dogs','out?']
> c = zip(a,b)
> 
> print c
> [('who', 'dogs'), ('let', 'out?')]
> 
> 
> Wouldn't it be better to return an empty element than silently kill your 
> data?
> 
> [('who', 'dogs'), ('let', 'out?'), ('the', '')]

>>> dfs_zip([1, 2, 3], [4, 5])
[(1, 4), (2, 5), (3, '')]

No, that's not much better, thanks.

In the face of ambiguity, refuse the temptation to guess.

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#108415

DFS <nospam@dfs.com> writes:
> Edit: I see they addressed this in 3.5 (maybe earlier), with an option:
> "itertools.zip_longest(*iterables, fillvalue=None)

This is available in 2.7 as itertools.izip_longest

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