import re


def latin_lower(s):
    """ Convert string to lower case,
    replace all non-latin or non-digit symbols with dashes,
    deduplicate and trim dashes
    """

    result = s.lower()
    result = re.sub("[^a-z0-9]", '-', result)
    result = re.sub("-+", '-', result)
    result = re.sub("^-", '', result)
    result = re.sub("-$", '', result)

    return result;