dtformat_regexp.py

# coding: utf-8
import re

_02 = (lambda s: '{0:0>2}'.format(s))
_03 = (lambda s: '{0:0>3}'.format(s))

MAP = {
    '%a': r'(Sun|Mon|Tue|Wed|Thu|Fri|Sat)',
    '%A': r'(Sunday|Monday|Tuesday|Wednesday|Thursday|Friday|Saturday)',
    '%w': r'([0-6]{1})',
    '%d': r'({})'.format('|'.join(map(_02, range(1, 32)))),
    '%b': r'(Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)',
    '%B': r'(January|February|March|April|May|June|July|August|September|October|November|December)',
    '%m': r'({})'.format('|'.join(map(_02, range(1, 13)))),
    '%y': r'(\d{2})',
    '%Y': r'(\d{4})',
    '%H': r'({})'.format('|'.join(map(_02, range(1, 25)))),
    '%I': r'({})'.format('|'.join(map(_02, range(1, 13)))),
    '%p': r'(AM|PM)',
    '%M': r'({})'.format('|'.join(map(_02, range(1, 61)))),
    '%S': r'({})'.format('|'.join(map(_02, range(1, 61)))),
    '%s': r'(-?\d{1,12})',
    '%f': r'(\d{6})',
    '%z': r'([-+]\d{4})',
    '%Z': r'(.{0}|[A-Z]{3})',
    '%j': r'({})'.format('|'.join(map(_03, range(1, 367)))),
    '%U': r'({})'.format('|'.join(map(_02, range(0, 53)))),
    '%W': r'({})'.format('|'.join(map(_02, range(0, 53)))),
}


class CodeCannotConvert(Exception):
    pass


def dtregexp_replace(s):
    if re.search(r'(%c|%x|%X)', s):
        raise CodeCannotConvert(s)
    for a, b in MAP.items():
        s = s.replace(a, b)
    return s