indexing
	description: "Packed boolean strings"
	status: "See notice at end of class"
	names: packed_booleans
	access: index
	representation: array
	size: fixed
	date: "$Date$"
	revision: "$Revision$"

class interface
	BOOL_STRING

create

	make (n: INTEGER)
			-- Allocate area of n booleans.
		require
			non_negative_size: n >= 0
		ensure
			correct_allocation: count = n

feature -- Initialization

	make (n: INTEGER)
			-- Allocate area of n booleans.
		require
			non_negative_size: n >= 0
		ensure
			correct_allocation: count = n

feature -- Access

	item (i: INTEGER): BOOLEAN
			-- Boolean at i-th position,
			-- beginning at left, 1 origin
		require
			index_large_enough: 1 <= i
			index_small_enough: i <= count

feature -- Measurement

	count: INTEGER
			-- Number of boolean in the area.

feature -- Element change

	all_false
			-- Set all booleans to false.

	all_true
			-- Set all booleans to true.

	put (v: like item; i: INTEGER)
			-- Put boolean v at i-th position
			-- beginning at left, 1 origin.
		require
			index_large_enough: 1 <= i
			index_small_enough: i <= count

feature -- Basic operations

	left_shifted (n: INTEGER): like Current
			-- Left shifted 'Current' set, by n positions
		require
			non_negative_shift: n >= 0

	right_shifted (n: INTEGER): like Current
			-- Right shifted 'Current' set, by n positions
		require
			non_negative_shift: n >= 0

	infix "and" (other: like Current): like Current
			-- Logical and of 'Current' and other
		require
			other_not_void: other /= void
			same_size: other.count = count

	prefix "not": like Current
			-- Negation of 'Current'

	infix "or" (other: like Current): like Current
			-- Logical or of 'Current' and other
		require
			other_not_void: other /= void
			same_size: other.count = count

	infix "xor" (other: like Current): like Current
			-- Logical exclusive or of 'Current' and other
		require
			other_not_void: other /= void
			same_size: other.count = count

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 BOOL_STRING