    indexing
    	description: "Command manager which is able to retrieve the command associated to a Windows message."
    	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
    	WEL_COMMAND_MANAGER

    create
    	make
    			-- Make a command manager.

    feature -- Initialization

    	accommodate (n: INTEGER_32)
    			-- Reallocate table with enough space for `n' items;
    			-- keep all current items.
    			-- (from HASH_TABLE)
    		require -- from HASH_TABLE
    			n >= 0
    		ensure -- from HASH_TABLE
    			count_not_changed: count = old count
    			slot_count_same_as_count: used_slot_count = count
    			breathing_space: count < capacity * initial_occupation

    	make
    			-- Make a command manager.

    	hash_table_make (n: INTEGER_32)
    			-- Allocate hash table for at least `n' items.
    			-- The table will be resized automatically
    			-- if more than `n' items are inserted.
    			-- (from HASH_TABLE)
    		ensure -- from HASH_TABLE
    			breathing_space: n < capacity * initial_occupation
    			minimum_space: minimum_capacity < capacity * initial_occupation
    			more_than_minimum: capacity >= minimum_capacity
    			no_status: not special_status

    feature -- Access

    	current_keys: ARRAY [INTEGER_32]
    			-- New array containing actually used keys, from 1 to count
    			-- (from HASH_TABLE)
    		ensure -- from HASH_TABLE
    			good_count: Result.count = count

    	cursor: CURSOR
    			-- Current cursor position
    			-- (from HASH_TABLE)
    		ensure -- from HASH_TABLE
    			cursor_not_void: Result /= Void

    	found_item: WEL_COMMAND_EXEC
    			-- Item, if any, yielded by last search operation
    			-- (from HASH_TABLE)

    	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)

    	has (key: INTEGER_32): BOOLEAN
    			-- Is there an item in the table with key `key'?
    			-- (from HASH_TABLE)
    		ensure then -- from HASH_TABLE
    			default_case: (key = computed_default_key) implies (Result = has_default)

    	has_item (v: WEL_COMMAND_EXEC): BOOLEAN
    			-- Does structure include `v'?
    			-- (Reference or object equality,
    			-- based on object_comparison.)
    			-- (from HASH_TABLE)
    		ensure -- from CONTAINER
    			not_found_in_empty: Result implies not is_empty

    	item alias "[]" (key: INTEGER_32): WEL_COMMAND_EXEC assign put
    			-- Item associated with `key', if present
    			-- otherwise default value of type `G'
    			-- Was declared in HASH_TABLE as synonym of infix "@".
    			-- (from HASH_TABLE)
    		require -- from TABLE
    			valid_key: valid_key (key)
    		ensure then -- from HASH_TABLE
    			default_value_if_not_present: (not (has (key))) implies (Result = computed_default_value)

    	item_for_iteration: WEL_COMMAND_EXEC
    			-- Element at current iteration position
    			-- (from HASH_TABLE)
    		require -- from HASH_TABLE
    			not_off: not off

    	key_for_iteration: INTEGER_32
    			-- Key at current iteration position
    			-- (from HASH_TABLE)
    		require -- from HASH_TABLE
    			not_off: not off
    		ensure -- from HASH_TABLE
    			at_iteration_position: Result = key_at (iteration_position)

    	infix "@" (key: INTEGER_32): WEL_COMMAND_EXEC assign put
    			-- Item associated with `key', if present
    			-- otherwise default value of type `G'
    			-- Was declared in HASH_TABLE as synonym of item.
    			-- (from HASH_TABLE)
    		require -- from TABLE
    			valid_key: valid_key (key)
    		ensure then -- from HASH_TABLE
    			default_value_if_not_present: (not (has (key))) implies (Result = computed_default_value)

    feature -- Measurement

    	capacity: INTEGER_32
    			-- Number of items that may be stored.
    			-- (from HASH_TABLE)

    	count: INTEGER_32
    			-- Number of items in table
    			-- (from HASH_TABLE)

    	occurrences (v: WEL_COMMAND_EXEC): INTEGER_32
    			-- Number of table items equal to `v'.
    			-- (from HASH_TABLE)
    		ensure -- from BAG
    			non_negative_occurrences: Result >= 0

    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
    			-- Does table contain the same information as `other'?
    			-- (from HASH_TABLE)
    		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

    	after: BOOLEAN
    			-- Is cursor past last item?
    			-- Was declared in HASH_TABLE as synonym of off.
    			-- (from HASH_TABLE)
    		ensure -- from HASH_TABLE
    			definition: Result = ((not has_default and (iteration_position >= capacity)) or (has_default and (iteration_position = (capacity + 1))))

    	changeable_comparison_criterion: BOOLEAN
    			-- May object_comparison be changed?
    			-- (Answer: yes by default.)
    			-- (from CONTAINER)

    	conflict: BOOLEAN
    			-- Did last operation cause a conflict?
    			-- (from HASH_TABLE)

    	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

    	exists (message: INTEGER_32): BOOLEAN
    			-- Does a command associated to `message' exist?
    		require
    			positive_message: message >= 0

    	extendible: BOOLEAN is True
    			-- May new items be added? (Answer: yes.)
    			-- (from HASH_TABLE)

    	found: BOOLEAN
    			-- Did last operation find the item sought?
    			-- (from HASH_TABLE)

    	full: BOOLEAN is False
    			-- Is structure filled to capacity? (Answer: no.)
    			-- (from HASH_TABLE)

    	inserted: BOOLEAN
    			-- Did last operation insert an item?
    			-- (from HASH_TABLE)

    	is_empty: BOOLEAN
    			-- Is structure empty?
    			-- (from FINITE)
    		require -- from  CONTAINER
    			True

    	is_inserted (v: WEL_COMMAND_EXEC): BOOLEAN
    			-- Has `v' been inserted by the most recent insertion?
    			-- (By default, the value returned is equivalent to calling
    			-- `has (v)'. However, descendants might be able to provide more
    			-- efficient implementations.)
    			-- (from COLLECTION)

    	not_found: BOOLEAN
    			-- Did last operation fail to find the item sought?
    			-- (from HASH_TABLE)

    	object_comparison: BOOLEAN
    			-- Must search operations use equal rather than `='
    			-- for comparing references? (Default: no, use `='.)
    			-- (from CONTAINER)

    	off: BOOLEAN
    			-- Is cursor past last item?
    			-- Was declared in HASH_TABLE as synonym of after.
    			-- (from HASH_TABLE)
    		ensure -- from HASH_TABLE
    			definition: Result = ((not has_default and (iteration_position >= capacity)) or (has_default and (iteration_position = (capacity + 1))))

    	prunable: BOOLEAN
    			-- May items be removed? (Answer: yes.)
    			-- (from HASH_TABLE)

    	removed: BOOLEAN
    			-- Did last operation remove an item?
    			-- (from HASH_TABLE)

    	replaced: BOOLEAN
    			-- Did last operation replace an item?
    			-- (from HASH_TABLE)

    	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))

    	valid_cursor (c: CURSOR): BOOLEAN
    			-- Can cursor be moved to position `c'?
    			-- (from HASH_TABLE)
    		require -- from HASH_TABLE
    			c_not_void: c /= Void

    	valid_key (k: INTEGER_32): BOOLEAN
    			-- Is `k' a valid key?
    			-- (Answer: always yes for hash tables in this version)
    			-- (from HASH_TABLE)
    		require -- from  TABLE
    			True
    		ensure then -- from HASH_TABLE
    			Result

    feature -- Status setting

    	compare_objects
    			-- Ensure that future search operations will use equal
    			-- rather than `=' for comparing references.
    			-- (from CONTAINER)
    		require -- from CONTAINER
    			changeable_comparison_criterion: changeable_comparison_criterion
    		ensure -- from CONTAINER
    			object_comparison

    	compare_references
    			-- Ensure that future search operations will use `='
    			-- rather than equal for comparing references.
    			-- (from CONTAINER)
    		require -- from CONTAINER
    			changeable_comparison_criterion: changeable_comparison_criterion
    		ensure -- from CONTAINER
    			reference_comparison: not object_comparison

    feature -- Cursor movement

    	forth
    			-- Advance cursor to next occupied position,
    			-- or off if no such position remains.
    			-- (from HASH_TABLE)
    		require -- from HASH_TABLE
    			not_off: not off

    	go_to (c: CURSOR)
    			-- Move to position `c'.
    			-- (from HASH_TABLE)
    		require -- from HASH_TABLE
    			c_not_void: c /= Void
    			valid_cursor: valid_cursor (c)

    	search (key: INTEGER_32)
    			-- Search for item of key `key'.
    			-- If found, set found to true, and set
    			-- found_item to item associated with `key'.
    			-- (from HASH_TABLE)
    		ensure -- from HASH_TABLE
    			found_or_not_found: found or not_found
    			item_if_found: found implies (found_item = content.item (position))

    	start
    			-- Bring cursor to first position.
    			-- (from HASH_TABLE)

    feature -- Element change

    	extend (new: WEL_COMMAND_EXEC; key: INTEGER_32)
    			-- Assuming there is no item of key `key',
    			-- insert `new' with `key'.
    			-- Set inserted.
    			--
    			-- To choose between various insert/replace procedures,
    			-- see `instructions' in the Indexing clause.
    			-- (from HASH_TABLE)
    		require -- from HASH_TABLE
    			not_present: not has (key)
    		ensure -- from HASH_TABLE
    			inserted: inserted
    			insertion_done: item (key) = new
    			one_more: count = old count + 1
    			same_slot_count_or_one_more_unless_reallocated: (used_slot_count = old used_slot_count) or (used_slot_count = old used_slot_count + 1) or (used_slot_count = count)
    			default_property: has_default = ((key = computed_default_key) or (old has_default))

    	fill (other: CONTAINER [WEL_COMMAND_EXEC])
    			-- Fill with as many items of `other' as possible.
    			-- The representations of `other' and current structure
    			-- need not be the same.
    			-- (from COLLECTION)
    		require -- from COLLECTION
    			other_not_void: other /= Void
    			extendible: extendible

    	hash_table_force (new: WEL_COMMAND_EXEC; key: INTEGER_32)
    			-- Update table so that `new' will be the item associated
    			-- with `key'.
    			-- If there was an item for that key, set found
    			-- and set found_item to that item.
    			-- If there was none, set not_found and set
    			-- found_item to the default value.
    			--
    			-- To choose between various insert/replace procedures,
    			-- see `instructions' in the Indexing clause.
    			-- (from HASH_TABLE)
    		require else -- from HASH_TABLE
    			True
    		ensure then -- from HASH_TABLE
    			insertion_done: item (key) = new
    			now_present: has (key)
    			found_or_not_found: found or not_found
    			not_found_if_was_not_present: not_found = not (old has (key))
    			same_count_or_one_more: (count = old count) or (count = old count + 1)
    			same_slot_count_or_one_more_unless_reallocated: (used_slot_count = old used_slot_count) or (used_slot_count = old used_slot_count + 1) or (used_slot_count = count)
    			found_item_is_old_item: found implies (found_item = old (item (key)))
    			default_value_if_not_found: not_found implies (found_item = computed_default_value)
    			default_property: has_default = ((key = computed_default_key) or ((key /= computed_default_key) and (old has_default)))

    	merge (other: HASH_TABLE [WEL_COMMAND_EXEC, INTEGER_32])
    			-- Merge `other' into Current. If `other' has some elements
    			-- with same key as in `Current', replace them by one from
    			-- `other'.
    			-- (from HASH_TABLE)
    		require -- from HASH_TABLE
    			other_not_void: other /= Void
    		ensure -- from HASH_TABLE
    			inserted: other.current_keys.linear_representation.for_all (agent has)

    	put (new: WEL_COMMAND_EXEC; key: INTEGER_32)
    			-- Insert `new' with `key' if there is no other item
    			-- associated with the same key.
    			-- Set inserted if and only if an insertion has
    			-- been made (i.e. `key' was not present).
    			-- If so, set position to the insertion position.
    			-- If not, set conflict.
    			-- In either case, set found_item to the item
    			-- now associated with `key' (previous item if
    			-- there was one, `new' otherwise).
    			--
    			-- To choose between various insert/replace procedures,
    			-- see `instructions' in the Indexing clause.
    			-- (from HASH_TABLE)
    		require -- from TABLE
    			valid_key: valid_key (key)
    		ensure then -- from HASH_TABLE
    			conflict_or_inserted: conflict or inserted
    			insertion_done: inserted implies item (key) = new
    			now_present: inserted implies has (key)
    			one_more_if_inserted: inserted implies (count = old count + 1)
    			unchanged_if_conflict: conflict implies (count = old count)
    			same_item_if_conflict: conflict implies (item (key) = old (item (key)))
    			slot_count_unchanged_if_conflict: conflict implies (used_slot_count = old used_slot_count)
    			found_item_associated_with_key: found_item = item (key)
    			new_item_if_inserted: inserted implies (found_item = new)
    			old_item_if_conflict: conflict implies (found_item = old (item (key)))
    			default_property: has_default = ((inserted and (key = computed_default_key)) or ((conflict or (key /= computed_default_key)) and (old has_default)))

    	replace (new: WEL_COMMAND_EXEC; key: INTEGER_32)
    			-- Replace item at `key', if present,
    			-- with `new'; do not change associated key.
    			-- Set replaced if and only if a replacement has been made
    			-- (i.e. `key' was present); otherwise set not_found.
    			-- Set found_item to the item previously associated
    			-- with `key' (default value if there was none).
    			--
    			-- To choose between various insert/replace procedures,
    			-- see `instructions' in the Indexing clause.
    			-- (from HASH_TABLE)
    		ensure -- from HASH_TABLE
    			replaced_or_not_found: replaced or not_found
    			insertion_done: replaced implies item (key) = new
    			no_change_if_not_found: not_found implies item (key) = old (item (key))
    			found_item_is_old_item: found_item = old (item (key))

    	replace_key (new_key: INTEGER_32; old_key: INTEGER_32)
    			-- If there is an item of key `old_key' and no item of key
    			-- `new_key', replace the former's key by `new_key',
    			-- set replaced, and set found_item to the item
    			-- previously associated with `old_key'.
    			-- Otherwise set not_found or conflict respectively.
    			-- If conflict, set found_item to the item previously
    			-- associated with `new_key'.
    			--
    			-- To choose between various insert/replace procedures,
    			-- see `instructions' in the Indexing clause.
    			-- (from HASH_TABLE)
    		ensure -- from HASH_TABLE
    			same_count: count = old count
    			replaced_or_conflict_or_not_found: replaced or conflict or not_found
    			old_absent: (replaced and not equal (new_key, old_key)) implies (not has (old_key))
    			new_present: (replaced or conflict) = has (new_key)
    			new_item: replaced implies (item (new_key) = old (item (old_key)))
    			not_found_implies_no_old_key: not_found implies old (not has (old_key))
    			conflict_iff_already_present: conflict = old (has (new_key))
    			not_inserted_if_conflict: conflict implies (item (new_key) = old (item (new_key)))
    			default_property: has_default = ((new_key = computed_default_key) or ((new_key /= computed_default_key) and (old has_default)))

    feature -- Removal

    	clear_all
    			-- Reset all items to default values; reset status.
    			-- (from HASH_TABLE)
    		require -- from COLLECTION
    			prunable: prunable
    		ensure -- from COLLECTION
    			wiped_out: is_empty
    		ensure then -- from HASH_TABLE
    			position_equal_to_zero: position = 0
    			count_equal_to_zero: count = 0
    			used_slot_count_equal_to_zero: used_slot_count = 0
    			has_default_set: not has_default
    			no_status: not special_status

    	hash_table_remove (key: INTEGER_32)
    			-- Remove item associated with `key', if present.
    			-- Set removed if and only if an item has been
    			-- removed (i.e. `key' was present);
    			-- if so, set position to index of removed element.
    			-- If not, set not_found.
    			-- Reset found_item to its default value if removed.
    			-- (from HASH_TABLE)
    		ensure -- from HASH_TABLE
    			removed_or_not_found: removed or not_found
    			not_present: not has (key)
    			one_less: found implies (count = old count - 1)
    			same_slot_count: used_slot_count = old used_slot_count
    			default_case: (key = computed_default_key) implies (not has_default)
    			non_default_case: (key /= computed_default_key) implies (has_default = old has_default)

    feature -- Conversion

    	linear_representation: ARRAYED_LIST [WEL_COMMAND_EXEC]
    			-- Representation as a linear structure
    			-- (from HASH_TABLE)
    		require -- from  CONTAINER
    			True
    		ensure then -- from HASH_TABLE
    			result_exists: Result /= Void
    			good_count: Result.count = count

    feature -- Duplication

    	copy (other: like Current)
    			-- Re-initialize from `other'.
    			-- (from HASH_TABLE)
    		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 -- Basic routines

    	force (command: WEL_COMMAND_EXEC; message: INTEGER_32)
    			-- Put `command' associated to `message'.
    		require
    			command_not_void: command /= Void
    			positive_message: message >= 0
    		ensure
    			exists: exists (message)

    	remove (message: INTEGER_32)
    			-- Remove the command associated to `message'.
    		require
    			positive_message: message >= 0
    		ensure
    			not_exists: not exists (message)

    feature -- Output

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

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

    	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
    		-- from HASH_TABLE
    	keys_not_void: keys /= Void
    	content_not_void: content /= Void
    	deleted_marks_not_void: deleted_marks /= Void
    	keys_same_capacity_plus_one: keys.count = capacity + 1
    	content_same_capacity_plus_one: content.count = capacity + 1
    	deleted_same_capacity: deleted_marks.count = capacity + 1
    	valid_iteration_position: off or truly_occupied (iteration_position)
    	control_non_negative: control >= 0
    	special_status: special_status = (conflict or inserted or replaced or removed or found or not_found)
    	max_occupation_meaningful: (max_occupation > 0) and (max_occupation < 1)
    	initial_occupation_meaningful: (initial_occupation > 0) and (initial_occupation < 1)
    	sized_generously_enough: initial_occupation < max_occupation
    	count_big_enough: 0 <= count
    	count_small_enough: count <= capacity
    	breathing_space: count <= capacity * max_occupation
    	count_no_more_than_slot_count: count <= used_slot_count
    	slot_count_big_enough: 0 <= count
    	slot_count_small_enough: used_slot_count <= capacity

    		-- from FINITE
    	empty_definition: is_empty = (count = 0)
    	non_negative_count: count >= 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 WEL_COMMAND_MANAGER