-- File:	MoniTool_Element.cdl
-- Created:	Fri Nov  4 10:59:26 1994
-- Author:	Christian CAILLET
--		<cky@anion>
---Copyright:	 Matra Datavision 1994


deferred class Element  from MoniTool  inherits TShared

    ---Purpose : a Element allows to map any kind of object as a Key for a Map.
    --           This works by defining, for a Hash Code, that of the real Key,
    --           not of the Element which acts only as an intermediate.
    --           When a Map asks for the HashCode of a Element, this one returns
    --           the code it has determined at creation time

uses CString, Type, Transient, AttrList from MoniTool

is

    SetHashCode (me : mutable; code : Integer)  is static protected;
    ---Purpose : Stores the HashCode which corresponds to the Value given to
    --           create the Mapper

    GetHashCode (me) returns Integer  is static;
    ---Purpose : Returns the HashCode which has been stored by SetHashCode
    --           (remark that HashCode could be deferred then be defined by
    --            sub-classes, the result is the same)

    Equates (me; other : Element) returns Boolean  is deferred;
    ---Purpose : Specific testof equallity : to be defined by each sub-class,
    --           must be False if Elements have not the same true Type, else
    --           their contents must be compared

    ValueType    (me) returns Type  is virtual;
    ---Purpose : Returns the Type of the Value. By default, returns the
    --           DynamicType of <me>, but can be redefined

    ValueTypeName (me) returns CString  is virtual;
    ---Purpose : Returns the name of the Type of the Value. Default is name
    --           of ValueType, unless it is for a non-handled object

    	-- --    Attributes

    ListAttr (me) returns AttrList;
    ---Purpose : Returns (readonly) the Attribute List
    ---C++ : return const &

    ChangeAttr (me : mutable) returns AttrList;
    ---Purpose : Returns (modifiable) the Attribute List
    ---C++ : return &

fields

    thecode : Integer;
    theattrib : AttrList;

end Element;