remove_comments.py

def remove_comments(line, pref="", ctx=None, escape=False):
    if line == "": return pref
    if ctx == "#" and line[0] != '\n':
        return remove_comments(line[1:], pref, ctx)
    if not ctx:
        if line[0] == "#": return remove_comments(line[1:], pref, '#')
        for c in ['"""', '"', "'"]:
            if line.startswith(c):
                # open context
                return remove_comments(line[len(c):], pref + c, c)
    if ctx and line.startswith(ctx):
        # close context
        if not escape:
            return remove_comments(line[len(ctx):], pref + ctx, None)
    # carry over context
    if ctx != '"""' and line[0] == '\n':
        ctx = None
    return remove_comments(line[1:], pref + line[0], ctx,
                           not escape and line[0] == '\\')

tests = ['', '1; #a', '1; 1', '"" #"', '"a; #b"', '"a; #b" #c', '"a; # d \n b # c"', '"""a #c \n b #d""" #e', '"\\"" # test', '""#a\n""#b']

for t in tests:
    print t, '->', remove_comments(t)