Best way to read delimited newlines in Python and drop newlines?

Question

I am trying to determine the best way to deal with getting rid of newlines when reading in newline-delimited files in Python.

What I came up with is the following code that includes throwaway code for testing.

import os def getfile(filename,results): f = open(filename) filecontents = f.readlines() for line in filecontents: foo = line.strip('\n') results.append(foo) return results blahblah = [] getfile('/tmp/foo',blahblah) for x in blahblah: print x 

Suggestions?

Answer 1

 lines = open(filename).read().splitlines() 

Answer 2

Here, the generator does what you requested. In this case, using rstrip is sufficient and slightly faster than the strip.

 lines = (line.rstrip('\n') for line in open(filename)) 

However, you most likely want to use this to get rid of lagging spaces.

 lines = (line.rstrip() for line in open(filename)) 

Answer 3

 for line in file('/tmp/foo'): print line.strip('\n') 

Answer 4

What do you think of this approach?

 with open(filename) as data: datalines = (line.rstrip('\r\n') for line in data) for line in datalines: ...do something awesome... 

The expression of the generator avoids loading the entire file into memory, and with ensures closing the file

Answer 5

Just use generator expressions:

 blahblah = (l.rstrip() for l in open(filename)) for x in blahblah: print x 

I also want to advise you not to read the entire file in memory - a cycle with generators is much more efficient on large data sets.

Answer 6

I use this

 def cleaned( aFile ): for line in aFile: yield line.strip() 

Then I can do such things.

 lines = list( cleaned( open("file","r") ) ) 

Or, I can extend the cleaning with additional functions, for example, discard empty lines or skip comment lines or something else.

Answer 7

I would do it like this:

 f = open('test.txt') l = [l for l in f.readlines() if l.strip()] f.close() print l