anchor.diff:  
       }
   
  +    @override
  +    String toString() {
  +
  +        StringBuffer sb = new StringBuffer();
  +        statements.forEach((statement) => sb.write(statement));
  +
  +        return sb.toString();
  +
  +    }
  +
   }
   
   class Identifier extends Expression {
  
positive.code:     Identifier(this.token, this.value);
  
      @override
      String tokenLiteral() {
  
          return token.literal;
  
      }
  
  }
  
  
negative.code:     LetStatement(this.token);
  
      @override
      String tokenLiteral() => token.literal;
  
      @override
      String toString() => "$tokenLiteral $name = ${value ?? ''};";
  
  }
  
  