Tracking down WARNING: Expecting a number or something iterable, got undefined

Posted on Thu 31st, March 2016

• #1

DrAzzy

What things can generate this error?

Is there any way that I can find out what line this is ocurring on? I have this coming up in my animation code seemingly at random, and I can't seem to figure out what is failing and returning undefined.
• #2

Gordon

To be honest it could be anything - most likely is SPI/I2C write, or E.toXX... Something where you could feed in an array, string, or a number.

I guess realistically this should be an exception, and then you'd get a stack trace out of it. I'll see how easy it'd be to change.
• #3

Gordon

Ok, just changed this - so if you try and up to date build it should now fail with a stack trace pointing you to the error

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