The current gfo implementation allows to pass grid-like search spaces, similar to sklearn.

However, currently we cannot pass - but it would be desirable to:

• values that are not np.ndarray-s, but coercible, i.e., 1D array-likes. If passed (e.g., lists), they get coerced to np.ndarray internally
• union grids, such as in sklearn

More generally, it should not be too complicated to allow the full sklearn syntax to work - although coercion is probably much easier than supporting union grids.