Python 3: unpack inner lists in list comprehension

Posted by Beau Martínez on Stack Overflow See other posts from Stack Overflow or by Beau Martínez
Published on 2010-04-06T16:05:05Z Indexed on 2010/04/06 16:23 UTC
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python-3.x

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regex

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list-comprehension

I'm running the following code on a list of strings to return a list of its words:

words = [re.split('\\s+', line) for line in lines]

However, I end up getting something like:

[['import', 're', ''], ['', ''], ['def', 'word_count(filename):', ''], ...]

As opposed to the desired:

['import', 're', '', '', '', 'def', 'word_count(filename):', '', ...]

How can I unpack the lists re.split('\\s+', line) produces in the above list comprehension? Naïvely, I tried using * but that doesn't work.

(I'm looking for a simple and Pythonic way of doing; I was tempted to write a function but I'm sure the language accommodates for this issue.)

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