| Class DS_CURSOR |
indexing
description:
"Cursors for data structure traversals"
library: "Gobo Eiffel Structure Library"
author: "Eric Bezault <ericb@gobosoft.com>"
copyright: "Copyright (c) 1999, Eric Bezault and others"
license: "Eiffel Forum License v2 (see forum.txt)"
deferred class interface
DS_CURSOR [G]
feature -- Access
item: G -- Item at cursor position require not_off: not off deferredcontainer: DS_TRAVERSABLE [G] -- Data structure traversed deferred
feature -- Status report
off: BOOLEAN -- Is there no item at cursor position? deferredsame_position (other: like Current): BOOLEAN -- Is current cursor at same position as other? require other_not_void: other /= Void deferred
feature -- Cursor movement
go_to (other: like Current)
-- Move cursor to other's position.
require
other_not_void: other /= Void
valid_cursor: container.valid_cursor (other)
deferred
ensure
same_position: same_position (other)
feature -- Comparison
is_equal (other: like Current): BOOLEAN
-- Are other and current cursor at the same position?
-- (From GENERAL.)
require
other_not_void: other /= Void
ensure
consistent: standard_is_equal (other) implies Result
same_type: Result implies same_type (other)
symmetric: Result implies other.is_equal (Current)
feature -- Duplication
copy (other: like Current)
-- Copy other to current cursor.
-- (From GENERAL.)
require
other_not_void: other /= Void
type_identity: same_type (other)
ensure
is_equal: is_equal (other)
invariant
container_not_void: container /= Void empty_constraint: container.is_empty implies off
end -- class DS_CURSOR
|
Copyright © 1999, Eric
Bezault mailto:ericb@gobosoft.com http://www.gobosoft.com Last Updated: 23 July 1999 |