mfilt

#!/usr/bin/env python

import argparse
import re
import sys

parser = argparse.ArgumentParser(description=
        '''Filter some text with a regex, allowing matches to span multiple lines.
        
This tool is based on some ideas from Rob Pike's Sam editor:
http://doc.cat-v.org/plan_9/4th_edition/papers/sam/.
''')
parser.add_argument('-i', dest='ignore_case', action='store_true', help='ignore case')
parser.add_argument('-s', dest='sort', action='store_true', help='sort matches')
parser.add_argument('-r', dest='reverse', action='store_true', help='reverse (also works with sort)')
parser.add_argument('pattern', type=str, nargs=1)
parser.add_argument('filenames', type=str, nargs='*')
args = parser.parse_args()

pat = args.pattern[0]
rxflags = re.DOTALL
if args.ignore_case:
    rxflags |= re.IGNORECASE
rx = re.compile(pat, rxflags)
if len(args.filenames) == 0:
    contents = sys.stdin.read()
else:
    contents = ''
    for fn in args.filenames:
        with open(fn) as f:
            contents += f.read()
matches = rx.findall(contents)
if args.sort:
    matches.sort()
if args.reverse:
    matches.reverse()
for m in matches:
    whole = m
    if isinstance(m, tuple):
        whole = m[0]
    if whole.strip():
        print whole