clean_path

#!/usr/bin/env python3
"""Canonicalizes a $PATH variable. Removes duplicates and relative paths."""
# Bailey Forrest <baileycforrest@gmail.com>

from __future__ import print_function

import os
import sys

def printerr(*args, **kwargs):
    print(*args, file=sys.stderr, **kwargs)


def main():
    """Main function."""

    if len(sys.argv) != 2:
        printerr("Usage: {} path_var".format(sys.argv[0]))
        sys.exit(1)

    dirs = sys.argv[1].split(":")
    result = []
    elems = set()

    for directory in dirs:
        if directory == "":
            continue

        if directory[0] != "/":
            printerr("Skipping relative path '{}'".format(directory))
            continue

        if directory not in elems and os.path.isdir(directory):
            elems.add(directory)
            result.append(directory)

    print(":".join(result))

if __name__ == '__main__':
    main()