/** @brief The two groups where the children could be packed: the start-group and the end-group */
typedef enum Etk_Box_Group
{
   ETK_BOX_START,    /**< The start-group of children: the children in this group are displayed
                      * at the start (left or top) of the box */
   ETK_BOX_END,      /**< The end-group of children: the children in this group are displayed
                      * at the end (right or bottom) of the box */
} Etk_Box_Group;

/** @brief Describes how a child of the box expands and fills the space */
typedef enum Etk_Box_Fill_Policy
{
   ETK_BOX_NONE = 1 << 0,       /**< The child does not fill or expand */
   ETK_BOX_EXPAND = 1 << 1,     /**< The child will fill all the available space in its cell */
   ETK_BOX_FILL = 1 << 2,       /**< The cell containing the child will expand to take all the available space */
}