Linewise merge multiple files

fzip.py

#!/usr/bin/env python
import argparse
from glob import glob


def unique_file_list(*glob_strings):
    file_lists = map(glob, glob_strings)
    return list(set([item for sublist in file_lists for item in sublist]))


def main():
    parser = argparse.ArgumentParser(description='Linewise combine multiple files')
    parser.add_argument('globs', metavar='GLOB', nargs='+',
                        help='Glob matching 1 or more files')
    parser.add_argument('-d', '--delimiter', help="Delimiter used to join file lines", default='\t')

    args = parser.parse_args()
    file_names = unique_file_list(*args.globs)
    files = map(lambda file_name: open(file_name, 'r'), file_names)
    more_to_read = True
    while more_to_read:
        buffer = []
        for f in files:
            line = f.readline()
            if line:
                buffer.append(line.replace('\n', ''))
            else:
                more_to_read = False
        if more_to_read:
            print(args.delimiter.join(buffer))
        

if __name__ == '__main__':
    main()