anchor.diff:     ;
   
   property
  -   : name (('.' name) | '[' expression ']')*
  +   : propertyname (('.' name) | '[' expression ']')*
  +   ;
  +
  +propertyname
  +   : name
  +   | stringliteral
      ;
   
   list
  
positive.code:    ;
  
  programdecl
     : '@program' name ':' name statement + '.'
     ;
  
  verbdecl
  
negative.code:    ;
  
  describedecl
     : '@describe' property 'as' expression
     ;
  
  contentsdecl
  