Python equivalent of Perl's while (<>) {...}?

Question

I write a lot of little scripts that process files on a line-by-line basis. In Perl, I use

while (<>) {     do stuff; } 

This is handy because it doesn't care where the input comes from (a file or stdin).

In Python I use this

if len(sys.argv) == 2: # there's a command line argument     sys.stdin = file(sys.argv[1]) for line in sys.stdin.readlines():     do stuff 

which doesn't seem very elegant. Is there a Python idiom that easily handles file/stdin input?

Answer 1

The fileinput module in the standard library is just what you want:

import fileinput  for line in fileinput.input(): ... 

Answer 2

import fileinput for line in fileinput.input():     process(line) 

This iterates over the lines of all files listed in sys.argv[1:], defaulting to sys.stdin if the list is empty.