Performance: Single change triggers complete form rerender. about react-final-form-arrays HOT 6 CLOSED

Thank you for helping me out. I played around with the subscriptions and they are quite straight forward. I think mainly the object syntax had me slightly confused.

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@KeKs0r
You can use subscription api to avoid unnecessary updates.
see: https://github.com/final-form/react-final-form-arrays#subscription-fieldsubscription

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I am not sure how that subscriptions would look. Because, it theoretically needs to know about all of its items. But when changing one of the Single fields, I only want to rerender the single field.

Or maybe I am understanding the subscriptions wrong. Could you give me an example to achieve the same rerender behaviour as in: https://kx8qv67nk5.codesandbox.io/

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@KeKs0r
Ok, here is my forked one and I added subscriptions: https://codesandbox.io/s/vmnq88nm67

You can see how the rerendering optimized by checking "Highlight Updates" in the React chrome extension. It shows only one field that you typing is rerendered. Also, the stringified JSON in the <pre> rerendered because I added <FormSpy> which subscribe values.
Is this exactly what you want to achieve?

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Yes this was, what I was looking for. I am wondering, whether I am losing some rerenders, that are expected? Such as for pristine etc.?

But it looks very promising.

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I am wondering, whether I am losing some rerenders, that are expected? Such as for pristine etc.?

Yes, if you don't set any properties to subscription then <Form /> or <FieldArray /> won't rerender by changing form state. That's how subscription works.

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