Type of error is not kept when error goes from inside to outside the workerpool

[slimee]

Figure an error of "type" CalculationError

class CalculationError extends Error{};

And it's loaded and thrown from inside the workerpool:

throw new CalculationError();

The error propagates from inside the workerpool context to the caller context.

The statement error instanceof CalculationError is:

• true inside the workerpool (and that's OK)
• false inside the caller context (and that's KO for me)

Do you notice this behavior? How should I preserve the type of errors thrown through the workerpool context? Regards

[josdejong]

The data transferred between the main process and a worker must be plain JSON. Any class instance information is lost. If you want to transfer a class instance, you'll need to put a serialization and deserialization logic of your own in place. If you want to transfer an error class, maybe you can let your function return an object { success, error } instead of throwing an exception, in combination with logic to turn your data and error message into plain JSON.