[Tutor] Removing lines in string-table

[Chris Smith]

On Tuesday, May 17, 2005, at 08:35 America/Chicago, 
tutor-request at python.org wrote:

> I have a string table (don't recall the right word used in Python
> right now) and would like to remove every 'cell' that contains a
> string '_thumb.jpg'. There are 1-> digits before the string if that
> matters. I made a for-loop that does what I want to:
>
> for line in fileNames:
>     if line[-10:] == '_thumb.jpg':
>         fileNames.remove(line)
>
> But I really doubt that it's not the best way to do this. So, any
> comments are really appreciated.
>

The above will not work if two successive lines contain the target 
text. When you remove the one, its neighbor "slides over" to take the 
place of the one removed and then when you proceed to the "next" line 
you are actually skipping the one that slid over.  This could be 
remedied with using indices to access the list, but perhaps a better 
approach is to use filter or a list comprehension to remove the target 
lines:

###
def myfilter(x):
	return not x.endswith('_thumb.jpg')
fileNames =filter(myfilter, fileNames)

# OR

fileNames =[x for x in fileNames if not x.endswith('_thumb.jpg')]
###

/c