Is there a better way to use strip() on a list of strings? - python [duplicate]

Answer 1

Some intriguing discussions on performance happened here, so let me provide a benchmark:

http://ideone.com/ldId8

noslice_map              : 0.0814900398254
slice_map                : 0.084676027298
noslice_comprehension    : 0.0927240848541
slice_comprehension      : 0.124806165695
iter_manual              : 0.133514881134
iter_enumerate           : 0.142778873444
iter_range               : 0.160353899002

So:

1. map(str.strip, my_list) is the fastest way, it's just a little bit faster than comperhensions.
   • Use map or itertools.imap if there's a single function that you want to apply (like str.split)
   • Use comprehensions if there's a more complicated expression
2. Manual iteration is the slowest way; a reasonable explanation is that it requires the interpreter to do more work and the efficient C runtime does less
3. Go ahead and assign the result like my_list[:] = map..., the slice notation introduces only a small overhead and is likely to spare you some bugs if there are multiple references to that list.
   • Know the difference between mutating a list and re-creating it.