indexing
	description: "[
		Special objects: homogeneous sequences of values, 
		used to represent arrays and strings
	]"
	status: "See notice at end of class"
	date: "$Date$"
	revision: "$Revision$"

class interface
	SPECIAL [T]

create

	make (n: INTEGER)
			-- Creates a special object for n entries.
		require
			non_negative_argument: n >= 0
		ensure
			area_allocated: count = n

feature -- Access

	index_of (v: T; start_position: INTEGER): INTEGER
			-- Index of first occurrence of item identical to v.
			-- -1 if none.
		require
			valid_start_position: start_position >= 0
		ensure
			found_or_not_found: Result = - 1 or else (Result >= 0 and then Result < count)

	item (i: INTEGER): T
			-- Item at i-th position
			-- (indices begin at 0)
		require
			index_big_enough: i >= 0
			index_small_enough: i < count

feature -- Measurement

	count: INTEGER
			-- Count of the special area

feature -- Status report

	all_default (upper: INTEGER): BOOLEAN
			-- Are all items between index 0 and upper
			-- set to default values?
		require
			min_upper: upper >= - 1
			max_upper: upper < count
		ensure
			valid_on_empty_area: upper = - 1 implies Result

	same_items (other: like Current; upper: INTEGER): BOOLEAN
			-- Do all items between index 0 and upper have
			-- same value?
		require
			min_upper: upper >= - 1
			max_upper: upper < count
			other_not_void: other /= void
			other_has_enough_items: upper < other.count
		ensure
			valid_on_empty_area: upper = - 1 implies Result

feature -- Element change

	put (v: T; i: INTEGER)
			-- Replace i-th item by v.
			-- (Indices begin at 0.)
		require
			index_big_enough: i >= 0
			index_small_enough: i < count

feature -- Removal

	clear_all
			-- Reset all items to default values.

feature -- Resizing

	resized_area (n: INTEGER): like Current
			-- Create a copy of Current with a count of n.
		require
			valid_new_count: n > count
		ensure
			result_not_void: Result /= void
			result_different_from_current: Result /= Current
			new_count: Result.count = n

invariant

		-- from ANY
	reflexive_equality: standard_is_equal (Current)
	reflexive_conformance: conforms_to (Current)

indexing
	library: "[
			EiffelBase: Library of reusable components for Eiffel.
	]"
	status: "[
			Copyright 1986-2001 Interactive Software Engineering (ISE).
			For ISE customers the original versions are an ISE product
			covered by the ISE Eiffel license and support agreements.
	]"
	license: "[
			EiffelBase may now be used by anyone as FREE SOFTWARE to
			develop any product, public-domain or commercial, without
			payment to ISE, under the terms of the ISE Free Eiffel Library
			License (IFELL) at http://eiffel.com/products/base/license.html.
	]"
	source: "[
			Interactive Software Engineering Inc.
			ISE Building
			360 Storke Road, Goleta, CA 93117 USA
			Telephone 805-685-1006, Fax 805-685-6869
			Electronic mail <info@eiffel.com>
			Customer support http://support.eiffel.com
	]"
	info: "[
			For latest info see award-winning pages: http://eiffel.com
	]"

end -- class SPECIAL