Re: do this with list comp?

From: Diez B. Roggisch (deets_noospaam_at_web.de)
Date: 12/13/03 

Date: Sat, 13 Dec 2003 15:46:15 +0100

John Hunter wrote:

>
> I want to replace all empty fields in a CSV line with 'NULL'.
>
> Here is a brute force way
>
> def fixline(line):
> ret = []
> for s in line.split(','):
> if not len(s): ret.append('NULL')
> else: ret.append(s)
> return ret
>
> line = 'John,Bill,,,Fred'
> print fixline(line)
> # ['John', 'Bill', 'NULL', 'NULL', 'Fred']
>
> I am wondering if there is a way to do it with list comprehensions. I
> know how I would do it with a ternary operator.....

This should work:

res = [[s, 'NULL'][not len(s)] for s in line.split(",")]

Diez

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