{{alias}}( str, len[, seq] )
    Truncates a string in the middle to a specified length.

    Parameters
    ----------
    str: string
        Input string.

    len: integer
        Output string length.

    seq: string (optional)
        Custom replacement sequence. Default: '...'.

    Returns
    -------
    out: string
        Truncated string.

    Examples
    --------
    > var str = 'beep boop';
    > var out = {{alias}}( str, 5 )
    'b...p'

    > out = {{alias}}( str, 5, '|' )
    'be|op'

    See Also
    --------