def dash_case(name):
    """
    Convert a camel case string to dash case.

    Example:
        >>> dash_case('SomeName')
        'some-name'
    """
    letters = []
    for c in name:
        if c.isupper() and letters and letters[-1] != '-':
            letters.append('-' + c.lower())
        else:
            letters.append(c.lower())
    return ''.join(letters).replace('_', '-')
