    indexing
    	description: "Rectangular areas."
    	legal: "See notice at end of class."
    	status: "See notice at end of class."
    	date: "$Date: 2006-01-22 18:25:44 -0800 (Sun, 22 Jan 2006) $"
    	revision: "$Revision: 56675 $"

    class interface
    	EV_RECTANGLE

    create
    	default_create
    			-- Process instances of classes with no creation clause.
    			-- (Default: do nothing.)
    			-- (from ANY)

    	make (a_x, a_y, a_width, a_height: INTEGER_32)
    			-- Initialize with `a_x', `a_y', `a_width', `a_height'.
    			-- Was declared in EV_RECTANGLE as synonym of set.
    		require
    			a_width_positive: a_width >= 0
    			a_height_positive: a_height >= 0

    	set (a_x, a_y, a_width, a_height: INTEGER_32)
    			-- Initialize with `a_x', `a_y', `a_width', `a_height'.
    			-- Was declared in EV_RECTANGLE as synonym of make.
    		require
    			a_width_positive: a_width >= 0
    			a_height_positive: a_height >= 0

    feature -- Access

    	bottom: INTEGER_32
    			-- Vertical position of bottom.

    	generating_type: STRING_8
    			-- Name of current object's generating type
    			-- (type of which it is a direct instance)
    			-- (from ANY)

    	generator: STRING_8
    			-- Name of current object's generating class
    			-- (base class of the type of which it is a direct instance)
    			-- (from ANY)

    	height: INTEGER_32
    			-- Height of `Current'.

    	left: INTEGER_32
    			-- Horizontal position of left side

    	right: INTEGER_32
    			--  Horizontal position of right side.

    	top: INTEGER_32
    			-- Vertical position of top.

    	width: INTEGER_32
    			-- Width of `Current'.

    	x: INTEGER_32
    			-- Horizontal position.

    	y: INTEGER_32
    			-- Vertical position.

    feature -- Comparison

    	frozen deep_equal (some: ANY; other: like arg #1): BOOLEAN
    			-- Are `some' and `other' either both void
    			-- or attached to isomorphic object structures?
    			-- (from ANY)
    		ensure -- from ANY
    			shallow_implies_deep: standard_equal (some, other) implies Result
    			both_or_none_void: (some = Void) implies (Result = (other = Void))
    			same_type: (Result and (some /= Void)) implies some.same_type (other)
    			symmetric: Result implies deep_equal (other, some)

    	frozen equal (some: ANY; other: like arg #1): BOOLEAN
    			-- Are `some' and `other' either both void or attached
    			-- to objects considered equal?
    			-- (from ANY)
    		ensure -- from ANY
    			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.is_equal (other))

    	is_equal (other: like Current): BOOLEAN
    			-- Is `other' attached to an object considered
    			-- equal to current object?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			symmetric: Result implies other.is_equal (Current)
    			consistent: standard_is_equal (other) implies Result

    	frozen standard_equal (some: ANY; other: like arg #1): BOOLEAN
    			-- Are `some' and `other' either both void or attached to
    			-- field-by-field identical objects of the same type?
    			-- Always uses default object comparison criterion.
    			-- (from ANY)
    		ensure -- from ANY
    			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.standard_is_equal (other))

    	frozen standard_is_equal (other: like Current): BOOLEAN
    			-- Is `other' attached to an object of the same type
    			-- as current object, and field-by-field identical to it?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			same_type: Result implies same_type (other)
    			symmetric: Result implies other.standard_is_equal (Current)

    feature -- Status report

    	conforms_to (other: ANY): BOOLEAN
    			-- Does type of current object conform to type
    			-- of `other' (as per Eiffel: The Language, chapter 13)?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void

    	has (c: EV_COORDINATE): BOOLEAN
    			-- Is `c' inside `Current'?
    		require
    			c_not_void: c /= Void

    	has_x_y (a_x, a_y: INTEGER_32): BOOLEAN
    			-- Is (`a_x', `a_y') inside `Current'?

    	intersects (other: like Current): BOOLEAN
    			-- Does `other' at least partially overlap `Current'?
    		require
    			other_not_void: other /= Void

    	lower_left: EV_COORDINATE
    			-- Lower-left corner of `Current'.
    		ensure
    			result_exists: Result /= Void
    			result_assigned: Result.x = x and then Result.y = y + height

    	lower_right: EV_COORDINATE
    			-- Lower-right corner of `Current'.
    		ensure
    			result_exists: Result /= Void
    			result_assigned: Result.x = x + width and then Result.y = y + height

    	same_type (other: ANY): BOOLEAN
    			-- Is type of current object identical to type of `other'?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			definition: Result = (conforms_to (other) and other.conforms_to (Current))

    	upper_left: EV_COORDINATE
    			-- Upper-left corner of `Current'.
    		ensure
    			result_exists: Result /= Void
    			result_assigned: Result.x = x and then Result.y = y

    	upper_right: EV_COORDINATE
    			-- Upper-right corner of `Current'.
    		ensure
    			result_exists: Result /= Void
    			result_assigned: Result.x = x + width and then Result.y = y

    feature -- Element change

    	grow_bottom (i: INTEGER_32)
    			-- Increment size by `i' to south.

    	grow_left (i: INTEGER_32)
    			-- Increment size by `i' to west.
    		require
    			width + i > 0

    	grow_right (i: INTEGER_32)
    			-- Increment size by `i' to east.

    	grow_top (i: INTEGER_32)
    			-- Increment size by `i' to north.
    		require
    			height + i > 0

    	include (a_x, a_y: INTEGER_32)
    			-- Enlarge so that `a_x', `a_y' is in `Current'.

    	include_point (c: EV_COORDINATE)
    			-- Enlarge so that `c' is in `Current'.
    		require
    			c_not_void: c /= Void
    		ensure
    			has_c: has (c)

    	merge (other: like Current)
    			-- Enlarge `Current' so that `other' fits inside.
    		require
    			other_not_void: other /= Void

    	move (a_x, a_y: INTEGER_32)
    			-- Move to `a_x' and `a_y'.
    		ensure
    			x_assigned: x = a_x
    			y_assigned: y = a_y

    	move_and_resize (a_x, a_y, a_width, a_height: INTEGER_32)
    			-- Move to `a_x' and `a_y' and resize to `a_width' and `a_height'.
    		require
    			a_width_positive: a_width >= 0
    			a_height_positive: a_height >= 0

    	resize (a_width, a_height: INTEGER_32)
    			-- Resize to `a_width' and `a_height'.
    		require
    			a_width_positive: a_width >= 0
    			a_height_positive: a_height >= 0
    		ensure
    			width_assigned: width = a_width
    			height_assigned: height = a_height

    	set_bottom (i: INTEGER_32)
    			-- Assign `i' to bottom.
    		require
    			i - y >= 0
    		ensure
    			assigned: bottom = i

    	set_height (new_height: INTEGER_32)
    			-- Assign `new_height' to height.
    		require
    			new_height_positive: new_height >= 0
    		ensure
    			height_assigned: height = new_height

    	set_left (i: INTEGER_32)
    			-- Assign `i' to left.
    		require
    			i <= right
    		ensure
    			assigned: left = i
    			right_same: right = old right

    	set_right (i: INTEGER_32)
    			-- Assign `i' to right.
    		require
    			i - x >= 0
    		ensure
    			assigned: right = i

    	set_top (i: INTEGER_32)
    			-- Assign `i' to top.
    		require
    			i <= bottom
    		ensure
    			assigned: top = i
    			bottom_same: bottom = old bottom

    	set_width (new_width: INTEGER_32)
    			-- Assign `new_width' to 'width'.
    		require
    			new_width_positive: new_width >= 0
    		ensure
    			width_assigned: width = new_width

    	set_x (new_x: INTEGER_32)
    			-- Assign `new_x' to x.
    		ensure
    			x_set: x = new_x

    	set_y (new_y: INTEGER_32)
    			-- Assign `new_y' to y.
    		ensure
    			y_set: y = new_y

    feature -- Duplication

    	copy (other: like Current)
    			-- Update current object using fields of object attached
    			-- to `other', so as to yield equal objects.
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    			type_identity: same_type (other)
    		ensure -- from ANY
    			is_equal: is_equal (other)

    	frozen deep_copy (other: like Current)
    			-- Effect equivalent to that of:
    			--		copy (`other' . deep_twin)
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			deep_equal: deep_equal (Current, other)

    	frozen deep_twin: like Current
    			-- New object structure recursively duplicated from Current.
    			-- (from ANY)
    		ensure -- from ANY
    			deep_equal: deep_equal (Current, Result)

    	frozen standard_copy (other: like Current)
    			-- Copy every field of `other' onto corresponding field
    			-- of current object.
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    			type_identity: same_type (other)
    		ensure -- from ANY
    			is_standard_equal: standard_is_equal (other)

    	frozen standard_twin: like Current
    			-- New object field-by-field identical to `other'.
    			-- Always uses default copying semantics.
    			-- (from ANY)
    		ensure -- from ANY
    			standard_twin_not_void: Result /= Void
    			equal: standard_equal (Result, Current)

    	frozen twin: like Current
    			-- New object equal to `Current'
    			-- twin calls copy; to change copying/twining semantics, redefine copy.
    			-- (from ANY)
    		ensure -- from ANY
    			twin_not_void: Result /= Void
    			is_equal: Result.is_equal (Current)

    feature -- Basic operations

    	frozen default: like Current
    			-- Default value of object's type
    			-- (from ANY)

    	frozen default_pointer: POINTER
    			-- Default value of type `POINTER'
    			-- (Avoid the need to write `p'.default for
    			-- some `p' of type `POINTER'.)
    			-- (from ANY)

    	default_rescue
    			-- Process exception for routines with no Rescue clause.
    			-- (Default: do nothing.)
    			-- (from ANY)

    	frozen do_nothing
    			-- Execute a null action.
    			-- (from ANY)

    feature -- Output

    	io: STD_FILES
    			-- Handle to standard file setup
    			-- (from ANY)

    	out: STRING_8
    			-- Return readable string.

    	print (some: ANY)
    			-- Write terse external representation of `some'
    			-- on standard output.
    			-- (from ANY)

    	frozen tagged_out: STRING_8
    			-- New string containing terse printable representation
    			-- of current object
    			-- Was declared in ANY as synonym of out.
    			-- (from ANY)

    feature -- Platform

    	operating_environment: OPERATING_ENVIRONMENT
    			-- Objects available from the operating system
    			-- (from ANY)

    invariant
    	width_positive: width >= 0
    	height_positive: height >= 0

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

    indexing
    	copyright: "Copyright (c) 1984-2006, Eiffel Software and others"
    	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
    	source: "[
    		Eiffel Software
    		356 Storke Road, Goleta, CA 93117 USA
    		Telephone 805-685-1006, Fax 805-685-6869
    		Website http://www.eiffel.com
    		Customer support http://support.eiffel.com
    	]"

    end -- class EV_RECTANGLE