anchor.diff:          { $declaration = def; }
           interfaceBody
           { def.setInterfaceBody($interfaceBody.interfaceBody); }
  -      //-> ^(INTERFACE_DEFINITION typeName interfaceParameters? interfaceBody)
         | 
           (
             typeSpecifier
  
positive.code:         SEMICOLON
          { $declaration.setEndToken($SEMICOLON); 
            expecting=-1; }
        //-> ^(INTERFACE_DECLARATION[$INTERFACE_DEFINITION] typeName interfaceParameters? typeSpecifier?)
        )
      ;
  
  
negative.code:         { expecting=-1; }
          { $declaration.setEndToken($SEMICOLON); }
        )
      ;
  
  inferredGetterArgument returns [AttributeArgument declaration]
  