re-filter.py

#
# Filter input to remove content matching regexp, then output to stdout.
#
# Example:
#   cat data.sql | python3 re-filter.py "CREATE TRIGGER.*?;"
#
import re
import sys

matcher = re.compile(sys.argv[1], re.MULTILINE | re.DOTALL | re.IGNORECASE)

positions = [0]

input_str = sys.stdin.read()
for m in matcher.finditer(input_str):
    positions.append(m.start())
    positions.append(m.end())

positions.append(len(input_str))

while positions:
    start = positions.pop(0)
    end = positions.pop(0)
    sys.stdout.write(input_str[start:end])