anchor.diff:  
   
   NUMBER
  -   : '$'? ('-' |'+' )? [0-9a-fA-F] + ('H' | 'h')?
  +   : '$'? ('-')? [0-9a-fA-F] + ('H' | 'h')?
      ;
   
   
  
positive.code:    | name 
     | string
     | ('(' expression ')')
     ;
  
  dollar
  
negative.code:    ;
  
  directive
     : argument? assemblerdirective expressionlist?
     ;
  
  assemblerdirective
  