[occt.git] / src / Dico / Dico_Dictionary.cdl

-- Created on: 1992-07-28
-- Created by: Christian CAILLET
-- Copyright (c) 1992-1999 Matra Datavision
-- Copyright (c) 1999-2012 OPEN CASCADE SAS
--
-- The content of this file is subject to the Open CASCADE Technology Public
-- License Version 6.5 (the "License"). You may not use the content of this file
-- except in compliance with the License. Please obtain a copy of the License
-- at http://www.opencascade.org and read it completely before using this file.
--
-- The Initial Developer of the Original Code is Open CASCADE S.A.S., having its
-- main offices at: 1, place des Freres Montgolfier, 78280 Guyancourt, France.
--
-- The Original Code and all software distributed under the License is
-- distributed on an "AS IS" basis, without warranty of any kind, and the
-- Initial Developer hereby disclaims all such warranties, including without
-- limitation, any warranties of merchantability, fitness for a particular
-- purpose or non-infringement. Please see the License for the specific terms
-- and conditions governing the rights and limitations under the License.


generic class Dictionary  from Dico  (TheItem as any)  inherits TShared

    ---Purpose : Defines an alphanumeric dictionary in a cellular way,
    --           corresponding to an indexed tree.
    --           (note that an "entry" is a cell with a value associated,
    --            other cells are accessed by dictionary nmanagenent only) 
    --           For each level, cells follow by "next" chaining.
    --           To pass to next level, cells follow by "sub" chaining
    --           
    --  Warning : Because of implementation as a tree of cells, beware about
    --           size of TheItem class if it is not identified by Handle) : if
    --           this size is big, it can cause problems of memory spending

uses Size, OStream, Integer, Boolean, Character, AsciiString --, Iterator

raises NoSuchObject


    	-- --   Nested class : Iterator (on Dictionary)   -- --

    class Iterator

    ---Purpose : Defines an iterator on a Dictionary
    --           Iteration is alphabetic (due to dictionary construction)
    --           Each entry is defined by its Name and its item Value
    --	         Remark : The stack used by the Iterator is able to give
    --	         complete name by scanning it

    uses Boolean, AsciiString  -- , StackItem , Dictionary

    raises NoSuchObject

    is

    	Create (acell : Dictionary) returns Iterator;
        ---Purpose : Creates an iterator which will work on all the dictionary
    
    	Create (acell : Dictionary; basename : CString) returns Iterator;
        ---Purpose : Creates an iterator which will consider only entries
        --           which name begin by the string given as basename (subpart)

    	Create (acell : Dictionary; basename : AsciiString) returns Iterator;
        ---Purpose : Creates an iterator which will consider only entries
        --           which name begin by the string given as basename (subpart)
        --           Same as above, but basename is String instead of CString
    
    	Start (me : in out)  is static;
    	---Purpose : Allows to Start a new Iteration from beginning
    
    	More (me : in out) returns Boolean  is static;
    	---Purpose : Returns True if there are more entries to return
    
    	Next (me : in out)  is static;
    	---Purpose : Go to the next entry
    	--           (if there is not, Value will raise an exception)
    
    	Value (me) returns any TheItem
    	---Purpose : Returns item value of current entry
    	    raises NoSuchObject  is static;
    	--           Exception raised if there is no current Item
    	---C++ : return const &
    
    	Name  (me) returns AsciiString
    	---Purpose : Returns name of current entry
    	    raises NoSuchObject  is static;
    	--           Exception raised if there is no current Item

    	AppendStack (me : in out; val : Dictionary)  is static private;
	---Purpose : Appends a new value to the Iteration Stack

    fields

    	thebase : Dictionary;
    	thename : AsciiString;    -- base name (if not empty)
    	thelast : StackItem; -- Iteration Stack
    	thenb   : Integer;
    	themore : Boolean;   -- More called before Next ?
    	theinit : Boolean;   -- current cell processed ?
    	thenext : Boolean;   -- unstack -> Next cell to choose

    end Iterator;


    private class StackItem  inherits TShared
    
    	---Purpose : Defines an Item for the Stack used by the Iterator

    --  uses Dictionary

    is
    
    	Create returns mutable StackItem;
	---Purpose : Creates a StackItem with no Previous one
    
    	Create (previous : mutable StackItem) returns mutable StackItem;
	---Purpose : Creates a StackItem with a Previous one

    	Previous (me) returns mutable StackItem  is static;
	---Purpose : Returns the Previous Item (is Null if no Previous defined)

    	Value (me) returns Dictionary  is static;
	---Purpose : Returns the Dictionary Cell corresponding to an Item

    	SetValue (me : mutable; cval : Dictionary)  is static;
	---Purpose : Sets a new Dictionary Cell as Value of an Item

     fields
     
     	thevalue : Dictionary;
	theprev  : StackItem;

    end StackItem;

is

    	    	-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
    	    	--                                           --
    	    	-- --  Description of Dictionary itself   -- --
    	    	--                                           --
    	    	-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
    	-- (methods having a String argument are duplicated String-CString)

    Create returns mutable Dictionary;
    ---Purpose : Creates a Dictionary cell.
    --           A Dictionary is always created then handled by its first cell
    --           After creating a Dictionary, user can call methods HasItem,
    --           Item, SetItem ... (internal cells and entries are also
    --           defined as objects from the same class)
    --           Also iteration can be made, by an Iterator on this Dictionary

    SetChar (me : mutable; car : Character)  is static private;
    ---Purpose : Defines cell's character (internal use, to build dict. tree)


    HasItem (me; name : CString; exact : Boolean = Standard_False)
    	returns Boolean  is static;
    ---Purpose : Returns True if an Item is bound to a Name in the Dictionnary
    --           <exact> : if True, commands exact matching
    --             if False, accept completion, only if ONE AND ONLY ONE
    --             Dictionnary Entry has <name> as beginning of its name

    HasItem (me; name : AsciiString; exact : Boolean = Standard_True)
    	returns Boolean  is static;
    ---Purpose : Works as above method but accepts a String from TCollection

    Item (me; name : CString; exact : Boolean = Standard_True)
    	returns any TheItem
    ---Purpose : Returns item bound to a name in the Dictionnary
    --           <exact> : same as for HasItem
    	raises NoSuchObject  is static;
    --           Error if <name> corresponds to no entry
    ---C++ : return const &

    Item (me; name : AsciiString; exact : Boolean = Standard_True)
        returns any TheItem  raises NoSuchObject  is static;
    ---Purpose : Works as above method but accepts a String from TCollection
    ---C++ : return const &


    GetItem (me; name : CString; anitem : out any TheItem;
    	     exact : Boolean = Standard_True)
    	returns Boolean  is static;
    ---Purpose : Gathers HasItem and Item, in a less regular but faster way
    --           If return is True, <anitem> is returned too, else it is not
    --           <exact> : same as for HasItem

    GetItem (me; name : AsciiString; anitem : out TheItem;
    	     exact : Boolean = Standard_True)
    	returns Boolean  is static;
    ---Purpose : Works as above method but accepts a String from TCollection
    
    SetItem (me : mutable; name : CString;
        anitem : any TheItem; exact : Boolean = Standard_True)  is static;
    ---Purpose : Binds an item to a dictionnary entry
    --           If <name> is already known in the dictionary, its value
    --           is changed. Else, the dictionary entry is created.
    --           If <exact> is given False, completion is tried, it is accepted
    --           If it gives a UNIQUE entry : hence this one will be modified
    --           Else, new entry is created with the exact name given

    SetItem (me : mutable; name : AsciiString;
    	anitem : any TheItem; exact : Boolean = Standard_True)  is static;
    ---Purpose : Works as above method but accepts a String from TCollection

    NewItem (me : mutable; name : CString; isvalued : out Boolean;
    	     exact : Boolean = Standard_True)  returns any TheItem
    ---Purpose : Returns the Item AS AN ADDRESS which corresponds to a Name,
    --           in order to be changed or set.
    --           If this name is not yet recorded, the Dictionary creates it.
    --           <isvalued> is returned True if the Item is recorded in the
    --           Dictionary, False else, in that case the Item is reserved and
    --           the name is noted as beeing valued now.
    	raises NoSuchObject  is static;
    --	         Error if no Item could be found or created (this means that
    --	         the Dictionary is corrupted and should be rebuilt)
    ---C++ : return &

    NewItem (me : mutable; name : AsciiString; isvalued : out Boolean;
    	     exact : Boolean = Standard_True)  returns any TheItem
    ---Purpose : Works as above method but accepts a String from TCollection
    	raises NoSuchObject  is static;
    --           Error as above
    ---C++ : return &

    RemoveItem (me : mutable; name : CString;
    	cln : Boolean = Standard_True; exact : Boolean = Standard_True)
    	returns Boolean  is static;
    ---Purpose : Removes a dictionary entry given by its name then Returns True
    --           If the entry does not exists, Does nothing then Returns False
    --           <exact> : as for HasItem, if completion works, the found entry
    --           is removed (else returned value is False)
    --           <cln> commands cleaning dictionary (to recover memory space)
    --           For an isolated call, it is recommanded to give it at True
    --           For a sequence of calls, rather give False, then call Clean

    RemoveItem (me : mutable; name : AsciiString;
    	cln : Boolean = Standard_True; exact : Boolean = Standard_True)
    	returns Boolean  is static;
    ---Purpose : Works as above method but accepts a String from TCollection

    Clean (me : mutable)  is static;
    ---Purpose : Deletes physically in one step the entries which were removed
    --           (can be used for a more efficient Memory Management : first
    --           Remove several Items (<cln> = False), then Clean the Memory)


    IsEmpty (me) returns Boolean  is static;
    ---Purpose : Returns True if no Item is recorded

    Clear (me : mutable)  is static;
    ---Purpose : Clears all the Dictionary : all recorded Items are removed

    Copy (me) returns mutable Dictionary  is static;
    ---Purpose : Copies the Dictionary as a Tree, without Copying the Items

    	-- --    Internal methods    -- --
    
    HasSub (me) returns Boolean  is static private;
    ---Purpose : Returns True if this cell has a subcell

    Sub (me) returns mutable Dictionary  is static private;
    ---Purpose : Returns subcell

    HasNext (me) returns Boolean  is static private;    
    ---Purpose : Returns True if this cell has a next cell

    Next (me) returns mutable Dictionary  is static private;
    ---Purpose : Returns next cell
    
    SetSub  (me : mutable; acell : mutable Dictionary)  is static private;
    ---Purpose : Defines subcell

    SetNext (me : mutable; acell : mutable Dictionary)  is static private;
    ---Purpose : Defines next cell

    SearchCell (me; name : CString; lmax : Size;
    	        car : Character; level : Size;
    	    	acell : out mutable Dictionary; reslev : out Size;
    	        stat : out Integer)  is static private;
    ---Purpose : Internal method used to get an entry from a given name

    NewCell (me : mutable; name : CString; namlen : Size;
    	     acell : in out mutable Dictionary; reslev : Size; stat : Integer)
	     is static private;
    ---Purpose : Internal method used to create a new entry for a name

    Complete (me; acell : out mutable Dictionary) returns Boolean  is static;
    ---Purpose : Internal routine used for completion (returns True if success)

    HasIt (me) returns Boolean  is static private;
    ---Purpose : Returns True if a cell has an associated item value

    It (me) returns any TheItem  is static private;
    ---Purpose : Returns item value associated to a cell
    ---C++ : return const &

    ItAdr (me : mutable) returns any TheItem  is static private;
    ---Purpose : Returns item address associated to a cell
    ---C++ : return &

    SetIt (me : mutable; anitem : any TheItem)  is static private;
    ---Purpose : Binds an item value to a cell

    DeclIt (me : mutable)  is static private;
    ---Purpose : Declares a cell as Valued : used by NewItem (when an Item
    --           is created if it did not exist and is returned)

    RemoveIt (me : mutable)  is static private;
    ---Purpose : Removes item bound to a cell (cancels effect of DeclIt)

    CellChar (me) returns Character  is static private;
    ---Purpose : Returns cell's character as a node feature

    GetCopied (me : mutable; fromcell : Dictionary)  is static private;
    ---Purpose : Performs Copy from an original <fromcell> to <me>
    --           Called by Copy

fields

    thecars : Character[4];
    thesub  : Dictionary;
    thenext : Dictionary;
    theitem : TheItem;

friends

    class Iterator

end Dictionary;
Commit	Line	Data
	1	-- Created on: 1992-07-28
	2	-- Created by: Christian CAILLET
	3	-- Copyright (c) 1992-1999 Matra Datavision
	4	-- Copyright (c) 1999-2012 OPEN CASCADE SAS
	5	--
	6	-- The content of this file is subject to the Open CASCADE Technology Public
	7	-- License Version 6.5 (the "License"). You may not use the content of this file
	8	-- except in compliance with the License. Please obtain a copy of the License
	9	-- at http://www.opencascade.org and read it completely before using this file.
	10	--
	11	-- The Initial Developer of the Original Code is Open CASCADE S.A.S., having its
	12	-- main offices at: 1, place des Freres Montgolfier, 78280 Guyancourt, France.
	13	--
	14	-- The Original Code and all software distributed under the License is
	15	-- distributed on an "AS IS" basis, without warranty of any kind, and the
	16	-- Initial Developer hereby disclaims all such warranties, including without
	17	-- limitation, any warranties of merchantability, fitness for a particular
	18	-- purpose or non-infringement. Please see the License for the specific terms
	19	-- and conditions governing the rights and limitations under the License.
	20
	21
	22
	23	generic class Dictionary from Dico (TheItem as any) inherits TShared
	24
	25	---Purpose : Defines an alphanumeric dictionary in a cellular way,
	26	-- corresponding to an indexed tree.
	27	-- (note that an "entry" is a cell with a value associated,
	28	-- other cells are accessed by dictionary nmanagenent only)
	29	-- For each level, cells follow by "next" chaining.
	30	-- To pass to next level, cells follow by "sub" chaining
	31	--
	32	-- Warning : Because of implementation as a tree of cells, beware about
	33	-- size of TheItem class if it is not identified by Handle) : if
	34	-- this size is big, it can cause problems of memory spending
	35
	36	uses Size, OStream, Integer, Boolean, Character, AsciiString --, Iterator
	37
	38	raises NoSuchObject
	39
	40
	41	-- -- Nested class : Iterator (on Dictionary) -- --
	42
	43	class Iterator
	44
	45	---Purpose : Defines an iterator on a Dictionary
	46	-- Iteration is alphabetic (due to dictionary construction)
	47	-- Each entry is defined by its Name and its item Value
	48	-- Remark : The stack used by the Iterator is able to give
	49	-- complete name by scanning it
	50
	51	uses Boolean, AsciiString -- , StackItem , Dictionary
	52
	53	raises NoSuchObject
	54
	55	is
	56
	57	Create (acell : Dictionary) returns Iterator;
	58	---Purpose : Creates an iterator which will work on all the dictionary
	59
	60	Create (acell : Dictionary; basename : CString) returns Iterator;
	61	---Purpose : Creates an iterator which will consider only entries
	62	-- which name begin by the string given as basename (subpart)
	63
	64	Create (acell : Dictionary; basename : AsciiString) returns Iterator;
	65	---Purpose : Creates an iterator which will consider only entries
	66	-- which name begin by the string given as basename (subpart)
	67	-- Same as above, but basename is String instead of CString
	68
	69	Start (me : in out) is static;
	70	---Purpose : Allows to Start a new Iteration from beginning
	71
	72	More (me : in out) returns Boolean is static;
	73	---Purpose : Returns True if there are more entries to return
	74
	75	Next (me : in out) is static;
	76	---Purpose : Go to the next entry
	77	-- (if there is not, Value will raise an exception)
	78
	79	Value (me) returns any TheItem
	80	---Purpose : Returns item value of current entry
	81	raises NoSuchObject is static;
	82	-- Exception raised if there is no current Item
	83	---C++ : return const &
	84
	85	Name (me) returns AsciiString
	86	---Purpose : Returns name of current entry
	87	raises NoSuchObject is static;
	88	-- Exception raised if there is no current Item
	89
	90	AppendStack (me : in out; val : Dictionary) is static private;
	91	---Purpose : Appends a new value to the Iteration Stack
	92
	93	fields
	94
	95	thebase : Dictionary;
	96	thename : AsciiString; -- base name (if not empty)
	97	thelast : StackItem; -- Iteration Stack
	98	thenb : Integer;
	99	themore : Boolean; -- More called before Next ?
	100	theinit : Boolean; -- current cell processed ?
	101	thenext : Boolean; -- unstack -> Next cell to choose
	102
	103	end Iterator;
	104
	105
	106	private class StackItem inherits TShared
	107
	108	---Purpose : Defines an Item for the Stack used by the Iterator
	109
	110	-- uses Dictionary
	111
	112	is
	113
	114	Create returns mutable StackItem;
	115	---Purpose : Creates a StackItem with no Previous one
	116
	117	Create (previous : mutable StackItem) returns mutable StackItem;
	118	---Purpose : Creates a StackItem with a Previous one
	119
	120	Previous (me) returns mutable StackItem is static;
	121	---Purpose : Returns the Previous Item (is Null if no Previous defined)
	122
	123	Value (me) returns Dictionary is static;
	124	---Purpose : Returns the Dictionary Cell corresponding to an Item
	125
	126	SetValue (me : mutable; cval : Dictionary) is static;
	127	---Purpose : Sets a new Dictionary Cell as Value of an Item
	128
	129	fields
	130
	131	thevalue : Dictionary;
	132	theprev : StackItem;
	133
	134	end StackItem;
	135
	136	is
	137
	138	-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
	139	-- --
	140	-- -- Description of Dictionary itself -- --
	141	-- --
	142	-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
	143	-- (methods having a String argument are duplicated String-CString)
	144
	145	Create returns mutable Dictionary;
	146	---Purpose : Creates a Dictionary cell.
	147	-- A Dictionary is always created then handled by its first cell
	148	-- After creating a Dictionary, user can call methods HasItem,
	149	-- Item, SetItem ... (internal cells and entries are also
	150	-- defined as objects from the same class)
	151	-- Also iteration can be made, by an Iterator on this Dictionary
	152
	153	SetChar (me : mutable; car : Character) is static private;
	154	---Purpose : Defines cell's character (internal use, to build dict. tree)
	155
	156
	157	HasItem (me; name : CString; exact : Boolean = Standard_False)
	158	returns Boolean is static;
	159	---Purpose : Returns True if an Item is bound to a Name in the Dictionnary
	160	-- <exact> : if True, commands exact matching
	161	-- if False, accept completion, only if ONE AND ONLY ONE
	162	-- Dictionnary Entry has <name> as beginning of its name
	163
	164	HasItem (me; name : AsciiString; exact : Boolean = Standard_True)
	165	returns Boolean is static;
	166	---Purpose : Works as above method but accepts a String from TCollection
	167
	168	Item (me; name : CString; exact : Boolean = Standard_True)
	169	returns any TheItem
	170	---Purpose : Returns item bound to a name in the Dictionnary
	171	-- <exact> : same as for HasItem
	172	raises NoSuchObject is static;
	173	-- Error if <name> corresponds to no entry
	174	---C++ : return const &
	175
	176	Item (me; name : AsciiString; exact : Boolean = Standard_True)
	177	returns any TheItem raises NoSuchObject is static;
	178	---Purpose : Works as above method but accepts a String from TCollection
	179	---C++ : return const &
	180
	181
	182	GetItem (me; name : CString; anitem : out any TheItem;
	183	exact : Boolean = Standard_True)
	184	returns Boolean is static;
	185	---Purpose : Gathers HasItem and Item, in a less regular but faster way
	186	-- If return is True, <anitem> is returned too, else it is not
	187	-- <exact> : same as for HasItem
	188
	189	GetItem (me; name : AsciiString; anitem : out TheItem;
	190	exact : Boolean = Standard_True)
	191	returns Boolean is static;
	192	---Purpose : Works as above method but accepts a String from TCollection
	193
	194	SetItem (me : mutable; name : CString;
	195	anitem : any TheItem; exact : Boolean = Standard_True) is static;
	196	---Purpose : Binds an item to a dictionnary entry
	197	-- If <name> is already known in the dictionary, its value
	198	-- is changed. Else, the dictionary entry is created.
	199	-- If <exact> is given False, completion is tried, it is accepted
	200	-- If it gives a UNIQUE entry : hence this one will be modified
	201	-- Else, new entry is created with the exact name given
	202
	203	SetItem (me : mutable; name : AsciiString;
	204	anitem : any TheItem; exact : Boolean = Standard_True) is static;
	205	---Purpose : Works as above method but accepts a String from TCollection
	206
	207	NewItem (me : mutable; name : CString; isvalued : out Boolean;
	208	exact : Boolean = Standard_True) returns any TheItem
	209	---Purpose : Returns the Item AS AN ADDRESS which corresponds to a Name,
	210	-- in order to be changed or set.
	211	-- If this name is not yet recorded, the Dictionary creates it.
	212	-- <isvalued> is returned True if the Item is recorded in the
	213	-- Dictionary, False else, in that case the Item is reserved and
	214	-- the name is noted as beeing valued now.
	215	raises NoSuchObject is static;
	216	-- Error if no Item could be found or created (this means that
	217	-- the Dictionary is corrupted and should be rebuilt)
	218	---C++ : return &
	219
	220	NewItem (me : mutable; name : AsciiString; isvalued : out Boolean;
	221	exact : Boolean = Standard_True) returns any TheItem
	222	---Purpose : Works as above method but accepts a String from TCollection
	223	raises NoSuchObject is static;
	224	-- Error as above
	225	---C++ : return &
	226
	227	RemoveItem (me : mutable; name : CString;
	228	cln : Boolean = Standard_True; exact : Boolean = Standard_True)
	229	returns Boolean is static;
	230	---Purpose : Removes a dictionary entry given by its name then Returns True
	231	-- If the entry does not exists, Does nothing then Returns False
	232	-- <exact> : as for HasItem, if completion works, the found entry
	233	-- is removed (else returned value is False)
	234	-- <cln> commands cleaning dictionary (to recover memory space)
	235	-- For an isolated call, it is recommanded to give it at True
	236	-- For a sequence of calls, rather give False, then call Clean
	237
	238	RemoveItem (me : mutable; name : AsciiString;
	239	cln : Boolean = Standard_True; exact : Boolean = Standard_True)
	240	returns Boolean is static;
	241	---Purpose : Works as above method but accepts a String from TCollection
	242
	243	Clean (me : mutable) is static;
	244	---Purpose : Deletes physically in one step the entries which were removed
	245	-- (can be used for a more efficient Memory Management : first
	246	-- Remove several Items (<cln> = False), then Clean the Memory)
	247
	248
	249	IsEmpty (me) returns Boolean is static;
	250	---Purpose : Returns True if no Item is recorded
	251
	252	Clear (me : mutable) is static;
	253	---Purpose : Clears all the Dictionary : all recorded Items are removed
	254
	255	Copy (me) returns mutable Dictionary is static;
	256	---Purpose : Copies the Dictionary as a Tree, without Copying the Items
	257
	258	-- -- Internal methods -- --
	259
	260	HasSub (me) returns Boolean is static private;
	261	---Purpose : Returns True if this cell has a subcell
	262
	263	Sub (me) returns mutable Dictionary is static private;
	264	---Purpose : Returns subcell
	265
	266	HasNext (me) returns Boolean is static private;
	267	---Purpose : Returns True if this cell has a next cell
	268
	269	Next (me) returns mutable Dictionary is static private;
	270	---Purpose : Returns next cell
	271
	272	SetSub (me : mutable; acell : mutable Dictionary) is static private;
	273	---Purpose : Defines subcell
	274
	275	SetNext (me : mutable; acell : mutable Dictionary) is static private;
	276	---Purpose : Defines next cell
	277
	278	SearchCell (me; name : CString; lmax : Size;
	279	car : Character; level : Size;
	280	acell : out mutable Dictionary; reslev : out Size;
	281	stat : out Integer) is static private;
	282	---Purpose : Internal method used to get an entry from a given name
	283
	284	NewCell (me : mutable; name : CString; namlen : Size;
	285	acell : in out mutable Dictionary; reslev : Size; stat : Integer)
	286	is static private;
	287	---Purpose : Internal method used to create a new entry for a name
	288
	289	Complete (me; acell : out mutable Dictionary) returns Boolean is static;
	290	---Purpose : Internal routine used for completion (returns True if success)
	291
	292	HasIt (me) returns Boolean is static private;
	293	---Purpose : Returns True if a cell has an associated item value
	294
	295	It (me) returns any TheItem is static private;
	296	---Purpose : Returns item value associated to a cell
	297	---C++ : return const &
	298
	299	ItAdr (me : mutable) returns any TheItem is static private;
	300	---Purpose : Returns item address associated to a cell
	301	---C++ : return &
	302
	303	SetIt (me : mutable; anitem : any TheItem) is static private;
	304	---Purpose : Binds an item value to a cell
	305
	306	DeclIt (me : mutable) is static private;
	307	---Purpose : Declares a cell as Valued : used by NewItem (when an Item
	308	-- is created if it did not exist and is returned)
	309
	310	RemoveIt (me : mutable) is static private;
	311	---Purpose : Removes item bound to a cell (cancels effect of DeclIt)
	312
	313	CellChar (me) returns Character is static private;
	314	---Purpose : Returns cell's character as a node feature
	315
	316	GetCopied (me : mutable; fromcell : Dictionary) is static private;
	317	---Purpose : Performs Copy from an original <fromcell> to <me>
	318	-- Called by Copy
	319
	320	fields
	321
	322	thecars : Character[4];
	323	thesub : Dictionary;
	324	thenext : Dictionary;
	325	theitem : TheItem;
	326
	327	friends
	328
	329	class Iterator
	330
	331	end Dictionary;