-- File:	Standard_ErrorHandler.cdl
-- Created:	Mon Sep 28 13:41:03 1992
-- Author:	Ramin BARRETO
--		<rba@sdsun4>
---Copyright:	 Matra Datavision 1992

class ErrorHandler from Standard

uses 
    Failure from Standard,
    Boolean from Standard,
    Address from Standard,
    PErrorHandler from Standard,
    Type from Standard
is
    Create returns ErrorHandler;
    	--- Purpose: Create a ErrorHandler (to be used with try{}catch(){}).
    	--           It uses the "setjmp" and "longjmp" routines. 
    	---Level: Advanced
    
    Destroy(me: in out);
    	---Purpose: Unlinks and checks if there is a raised exception.
    	---C++: alias ~
    	---Level: Advanced
        
    Unlink(me: in out);
    	---Purpose: Removes handler from the handlers list
	---Level: Advanced
    
    Catches(me: in out; aType: Type) returns Boolean;
    	---Purpose: Returns "True" if the caught exception has the same type 
    	--          or inherits from "aType"
    	---Level: Advanced
    
    Label(me: in out) returns JmpBuf from Standard;
    	---Purpose: Returns label for jump
    	---C++: inline
    	---C++: return &
    	---Level: Advanced
    
    Abort(myclass) is private;
    	---Purpose: A exception is raised but it is not yet caught. 
    	--          So Abort the current function and transmit the exception 
        --          to "calling routines".
	-- Warning: If no catch is prepared for this exception, it displays the
    	--          exception name and calls "exit(1)".
    	---Level: Internal
       
    Error(me) returns Failure;
    	---Purpose: Returns the current Error.

    LastCaughtError(myclass) returns Failure;
    	---Purpose: Returns the caught exception.
    	--    
    	---Level: Advanced
    
    Error(myclass; aError: Failure) is private;
    	---Purpose: Set the Error which will be transmitted to "calling routines".
    	---Level: Advanced
    
    IsInTryBlock(myclass) returns Boolean from  Standard;
    	---Purpose: Test if the code is currently running in a try block
    	---Level: Internal
	
    FindHandler(myclass; theStatus: HandlerStatus from Standard;
    	    	    	 theUnlink: Boolean       from Standard) 
    returns PErrorHandler from Standard is private;
    	---Purpose: Returns the current handler (Top in former implemntations)
    
fields

    myPrevious    : PErrorHandler from Standard;
    myCaughtError : Failure from Standard;
    myLabel       : JmpBuf from Standard;
    myStatus      : HandlerStatus from Standard;
    myThread      : ThreadId from Standard; 
    myCallbackPtr : Address from Standard;

friends
    class Failure,
    class ErrorHandlerCallback
    
end ErrorHandler from Standard;