| #! /usr/bin/env python |
| |
| # 1) Regular Expressions Test |
| # |
| # Read a file of (extended per egrep) regular expressions (one per line), |
| # and apply those to all files whose names are listed on the command line. |
| # Basically, an 'egrep -f' simulator. Test it with 20 "vt100" patterns |
| # against a five /etc/termcap files. Tests using more elaborate patters |
| # would also be interesting. Your code should not break if given hundreds |
| # of regular expressions or binary files to scan. |
| |
| # This implementation: |
| # - combines all patterns into a single one using ( ... | ... | ... ) |
| # - reads patterns from stdin, scans files given as command line arguments |
| # - produces output in the format <file>:<lineno>:<line> |
| # - is only about 2.5 times as slow as egrep (though I couldn't run |
| # Tom's test -- this system, a vanilla SGI, only has /etc/terminfo) |
| |
| import string |
| import sys |
| import re |
| |
| def main(): |
| pats = map(chomp, sys.stdin.readlines()) |
| bigpat = '(' + '|'.join(pats) + ')' |
| prog = re.compile(bigpat) |
| |
| for file in sys.argv[1:]: |
| try: |
| fp = open(file, 'r') |
| except IOError, msg: |
| print "%s: %s" % (file, msg) |
| continue |
| lineno = 0 |
| while 1: |
| line = fp.readline() |
| if not line: |
| break |
| lineno = lineno + 1 |
| if prog.search(line): |
| print "%s:%s:%s" % (file, lineno, line), |
| |
| def chomp(s): |
| return s.rstrip('\n') |
| |
| if __name__ == '__main__': |
| main() |
