Feature Suggestion: Include offset in "unexpected token" syntax error

[abierbaum]

Thanks for the great tool. It is working wonderfully.

I have machine configurations that work in code, but I want to visualize. So I paste them into the visualizer but invariably there is a syntax error to resolve. (for example removing typescript parameter types).

As it stands right now, I get a syntax error in the console about "Unexpected token X". It would be very helpful if the code that found the unexpected token could provide an offset number in the file and if correspondingly the definition editor window could show the current offset of the cursor. That would allow users to find the place where they have their errors much easier.