def primitiveIsValue(interp, s_frame, w_recv):
    """
    Tests if `w_recv` is a value.

    :param interp: The interpreter proxy.
    :param s_frame: The stack frame.
    :param w_recv: The receiver object.
    :returns: `w_true` if `w_recv` is a value.
    """
    if w_recv.is_value():
        return interp.space.w_true
    return interp.space.w_false