converting a sed / grep / awk / . . . bash pipe line into python

[Marc 'BlackJack' Rintsch]

On Tue, 02 Sep 2008 10:36:50 -0700, hofer wrote:

> sed 's/\.\..*//' \    ### remove '//' comments | sed 's/#.*//'

Comment does not match the code.  Or vice versa.  :-)

Untested:

from __future__ import with_statement
from itertools import ifilter, ifilterfalse, imap


def is_junk(line):
    line = line.rstrip()
    return not line or line.startswith('//') or line.startswith('#')


def extract_numbers(line):
    result = map(int, line.split()[:2])
    assert len(result) == 2
    return result


def main():
    with open('test.txt') as lines:
        clean_lines = ifilterfalse(is_junk, lines)
        pairs = imap(extract_numbers, clean_lines)
        print '\n'.join(b for a, b in pairs if a + b == 42)


if __name__ == '__main__':
    main()

Ciao,
	Marc 'BlackJack' Rintsch