[not tested]
oldfirst = this.first;
-> let oldfirst = this.first;
Thanks for finding this syntax flaw. Unfortunately, it's not the problem, I've updated the source code accordingly but the problems persists.
@HilmarSt started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
[not tested]
->
let oldfirst = this.first;