Function is_8601_date

17_regex/python/iso_8601.py:5–10

(line)

def is_8601_date(line):
    # optionally use functools.cache
    RE = re.compile(
        r"^(?:(?=[02468][048]00|[13579][26]00|[0-9][0-9]0[48]|[0-9][0-9][2468][048]|[0-9][0-9][13579][26])\d{4}(?:(-|)(?:(?:00[1-9]|0[1-9][0-9]|[1-2][0-9][0-9]|3[0-5][0-9]|36[0-6])|(?:01|03|05|07|08|10|12)(?:\1(?:0[1-9]|[12][0-9]|3[01]))?|(?:04|06|09|11)(?:\1(?:0[1-9]|[12][0-9]|30))?|02(?:\1(?:0[1-9]|[12][0-9]))?|W(?:0[1-9]|[1-4][0-9]|5[0-3])(?:\1[1-7])?))?)$|^(?:(?![02468][048]00|[13579][26]00|[0-9][0-9]0[48]|[0-9][0-9][2468][048]|[0-9][0-9][13579][26])\d{4}(?:(-|)(?:(?:00[1-9]|0[1-9][0-9]|[1-2][0-9][0-9]|3[0-5][0-9]|36[0-5])|(?:01|03|05|07|08|10|12)(?:\2(?:0[1-9]|[12][0-9]|3[01]))?|(?:04|06|09|11)(?:\2(?:0[1-9]|[12][0-9]|30))?|(?:02)(?:\2(?:0[1-9]|1[0-9]|2[0-8]))?|W(?:0[1-9]|[1-4][0-9]|5[0-3])(?:\2[1-7])?))?)$"
    )
    return RE.match(line)