anchor.diff:      ;   
       
   page
  -    : PAGE_SYM pseudoPage?
  -        LBRACE
  -            declaration SEMI (declaration SEMI)*
  -        RBRACE
  -    ;
  -    
  +    : PAGE_SYM (WS+ COLON pseudoPage)? WS* LBRACE WS* (declaration WS*)* RBRACE
  +    -> ^(PAGE_SYM pseudoPage? ^(DECLARATION declaration)*)
  +    ;
  +
   pseudoPage
  -    : COLON IDENT
  +    : IDENT
       ;
       
   combinator
  
positive.code: //          it belongs to the signified medium.
  //
  media
      : MEDIA_SYM medium (COMMA medium)*
          LBRACE
              ruleSet
          RBRACE
      ;
  
  // ---------    
  
negative.code: // Import.  Location of an external style sheet to include in the ruleset.
  //
  cssImport
      : IMPORT_SYM WS+ cssImportLocation  (WS+ medium (WS* COMMA WS* medium)*)? WS* SEMI
      -> ^(IMPORT cssImportLocation medium*)
      ;
      
  