Hi Felix. ISSUE: MODULE TestRect; TYPE Rect = RECORD END; PROCEDURE ( VAR this: Rect ) Clip*( CONST r: Rect ); END Clip; END TestRect. ERROR: ciclic definition in line 3 col 1 If in the procedure PROCEDURE ( VAR this: Rect ) Clip* ( CONST r: Rect ); to clean parameter (CONST r: Rect) or to replace with other type, everything works. --- Serge