anchor.diff:      ref(block);
   
     integerLiteral() => (
  -    anyIn(["-", "+"]).optional() &
  +    pattern("-+").optional() &
       digit().plus()
     ).flatten();
   
  
positive.code:     char("}");
  
    nativeCode() => string("```") &
      pattern("^```").star().flatten() &
      string("```");
  
    mapEntry() => ref(expressionItem) &
  
negative.code:   NEWLINE() => pattern('\n\r');
  
    singleLineComment() => string('//')
      & any().starLazy(ref(NEWLINE))
      & ref(NEWLINE).optional();
  
    declarations() => ref(declaration).separatedBy(char("\n"));
  