AmigActive 3/AACD03.BIN/AACD/Programming/sofa/archive/exml.lha/exml/examples/ebook/gobo_ext/ds_linked_tree.e

Text File | 1999-04-13 | 3KB | 135 lines

indexing
    description:"A linked tree based on the GOBO data structure library"
    status:        "See notice at end of class."
    author:        "Andreas Leitner"

class
    DS_LINKED_TREE [G]

inherit
    DS_TRAVERSABLE [G]
        redefine
            is_empty
        end

creation
    make
feature
    make is
        do

        end

    new_cursor: DS_LINKED_TREE_CURSOR [G] is
            -- New cursor for traversal
            -- (from DS_BILINEAR)
        do
            !! Result.make (Current)
        end;

    item (a_cursor: like new_cursor): G is
        do
            Result := a_cursor.item
        end

    put_root (v: G) is
        local
            new_cell: like root_cell
        do
            !! new_cell.make (v)
            root_cell := new_cell
        end


    root_cell: DS_LINKED_TREE_CELL [G]
feature -- Measurement

    count: INTEGER is
            -- Number of items in structure
        local
            cs: DS_LINKED_TREE_CURSOR [G]
        do
            --cs := new_cursor
            if
                is_empty
            then
                Result := 0
            else
                Result := 1
            end

        end
    is_empty: BOOLEAN is
        do
            Result := root_cell = Void
        end

feature -- Status report

feature -- Comparison

    is_equal (other: like Current): BOOLEAN is
            -- Is current structure equal to `other'?
        do
            check False end
        end

feature -- Removal

    wipe_out is
            -- Remove all items from structure.
        do
            root_cell := Void
        end

feature -- Duplication

    copy (other: like Current) is
            -- Copy `other' to list.
        do
            check False end
        end;


feature -- Children

    put_first_child (v: G; a_cursor: like new_cursor) is
            -- Add `v' to beginning of list.
        do
            a_cursor.children.put_first (v)
        end

    put_last_child (v: G; a_cursor: like new_cursor) is
            -- Add `v' to end of list.
        do
            a_cursor.children.put_last (v)
        end

    put_left_child (v: G; a_cursor: like new_cursor) is
            -- Add `v' to left of `a_cursor' position.
        do
            a_cursor.children.put_left (v, a_cursor.children_cursor)
        end

    put_right_child (v: G; a_cursor: like new_cursor) is
            -- Add `v' to right of `a_cursor' position.
        do
            a_cursor.children.put_right (v, a_cursor.children_cursor)
        end

end -- class DS_LINKED_TREE

--|-------------------------------------------------------------------------
--| eXML, Eiffel XML Parser Toolkit
--| Copyright (C) 1999  Andreas Leitner
--| See the file forum.txt included in this package for licensing info.
--|
--| Comments, Questions, Additions to this library? please contact:
--|
--| Andreas Leitner
--| Arndtgasse 1/3/5
--| 8010 Graz
--| Austria
--| email: [e-mail]
--| web: http://exml.dhs.org
--|-------------------------------------------------------------------------