I don’t know ReactJs. Clearly. As such I was stuck for about three days on why a function wouldn’t work correctly. I found out about how state works, and about binding functions in the constructor and all that. But I chopped what I had down to two identical functions doing identical things, and one of them worked. I wrote up a full Stackoverflow question and was about to post, when I saw it. I had this:

this.makeChoice - this.makeChoice.bind(this);
this.incrementCounter = this.incrementCounter.bind(this);

Do you see it? Can you tell which one worked?

Nothing flagged up that bloody hyphen, there’s no compilation, the runtime error was “I don’t know what this is”.

The rubber ducky, it works.