gtk:tree-list-row-depth (object)

object -- a gtk:tree-list-row object
depth -- an unsigned integer for the depth of the row

The accessor for the depth slot of the gtk:tree-list-row class returns the depth in the tree of the row. Rows that correspond to items in the root model have a depth of zero, rows corresponding to items of models of direct children of the root model have a depth of 1 and so on. The depth of a row never changes until the row is removed from its model at which point it will forever return 0.