is() not printing the message

> ## 142c142,143
> 
> ```
>       bool ret = ok(2 * fabs(left - right) / (fabs(left) + fabs(right)) < epsilon);
> ```
> ---
> 
> ```
>       bool ret = 2 * fabs(left - right) / (fabs(left) + fabs(right)) < epsilon;
>       ok(ret, message);
> ```

You forgot to modify is() to be like isnt()
