m3tk/src/toolmisc/M3Error.i3

INTERFACE M3Error;
************************************************************************* Copyright (C) Olivetti 1989 All Rights reserved Use and copy of this software and preparation of derivative works based upon this software are permitted to any person, provided this same copyright notice and the following Olivetti warranty disclaimer are included in any copy of the software or any modification thereof or derivative work therefrom made by any person. This software is made available AS IS and Olivetti disclaims all warranties with respect to this software, whether expressed or implied under any law, including all implied warranties of merchantibility and fitness for any purpose. In no event shall Olivetti be liable for any damages whatsoever resulting from loss of use, data or profits or otherwise arising out of or in connection with the use or performance of this software. ************************************************************************* 

IMPORT M3AST_LX, M3AST_AS;
IMPORT M3CSrcPos;
This interface supports the reporting and subsequent display of errors. Errors can be reported with reference to source position, for parsers, or by association with a node in the AST. Since any given node does not have a back pointer to the root, this interface defines the notion of the current unit, which must be set explicitly by the client before calling most procedures. 

PROCEDURE SetCu(cu: M3AST_AS.Compilation_Unit) RAISES {};
Since AST nodes may not contain a reference to the root, this procedure must be called to establish the unit, before any calls to the report procedures occur. 

TYPE
  ERROR_NODE = M3AST_AS.SRC_NODE;
The following procedures report errors. Errors are typically associated with AST nodes, with an implied unit and source position, and usually include identifier names. Consequently, 'message' may contain 'Fmt' %s specifiers. The method of error presentation is implementation dependent. 

PROCEDURE Report(n: ERROR_NODE; message: TEXT) RAISES {};
Reports an error associated with node 'n'. 

PROCEDURE ReportWithId(n: ERROR_NODE; message: TEXT;
    id1, id2, id3, id4: M3AST_LX.Symbol_rep := NIL) RAISES {};
Reports an error associated with node 'n', with optional arguments denoting identifier names that correspond with %s specifiers in 'message'. 

PROCEDURE ReportAtPos(pos: M3CSrcPos.T; message: TEXT) RAISES {};
If no node is available, e.g. some syntax errors, this associates an error with source position 'pos'. 

PROCEDURE Warn(n: ERROR_NODE; message: TEXT) RAISES {};
As 'Report', but only a warning. 

PROCEDURE WarnWithId(n: ERROR_NODE; message: TEXT;
    id1, id2, id3, id4: M3AST_LX.Symbol_rep := NIL) RAISES {};
As 'Report', but only a warning, with arguments as per WarnWithId. 

PROCEDURE SuppressWarnings(b := TRUE) RAISES {};
Switch off/on the interpretation of warning messages. 
 These procedures control when errors are presented and allow a client
   to be notified when an error is reported by one of the above procs. 


PROCEDURE Show(n: ERROR_NODE; forget := TRUE) RAISES {};

 Show (in some implementation dependent way) any errors on node 'n',
in the current unit. The error is forgotten unless 'forget = FALSE'. 

PROCEDURE ShowAll(n: ERROR_NODE; forget := TRUE) RAISES {};

 Calls 'Show' for the entire subtree rooted at 'n', in the current
   unit. 

TYPE
  Notification <: Notification_public;
  Notification_public = OBJECT
  METHODS
    notify(cu: M3AST_AS.Compilation_Unit; isError: BOOLEAN);
    (* "notify" will be called at least once for each unit in which
       an error is found. The "cu" argument will only be non-NIL if the
       error is not in the current unit, e.g. clashing declarations in
       imported interfaces. The second arg is FALSE if only a warning
       (i.e. from Warn(...))
    *)
  END;

PROCEDURE AddNotification(n: Notification);

PROCEDURE RemoveNotification(n: Notification);

END M3Error.