{{alias}}()
    Returns a list of diagonal element types.

    The output array contains the following types:

    - unit: elements along a diagonal are all equal to one.
    - non-unit: elements along a diagonal are not all equal to one.

    Returns
    -------
    out: Array<string>
        List of types.

    Examples
    --------
    > var out = {{alias}}()
    [ 'non-unit', 'unit' ]

    See Also
    --------