side effects and meta props for field

[ha1fstack]

1. add side effects prop to field

It's a very common pattern to trigger side effects when field event triggers.
For example, I might want to reset other field when some field's onChange event triggers.
It's not impossible to implement in current version but it would be great if it was exposed to Field's prop directly.

For workaround, I tried to add side effect to validators but validator always triggers on onSubmit so it caused unwanted behavior.

<form.Field
  name="foo"
  effects={{
    onChange: ({ fieldApi }) => fieldApi.form.setFieldValue('someOtherField', undefined),
    // same fields with validators
  }}
>

2. add meta prop to field

Another common pattern is when you want to inject additional meta context to field from form status.
It's possible with form.Subscribe but it would be much convenient as a prop.

<form.Field
  name="foo"
  meta={({ fieldApi }) => ({
    disabled: fieldApi.form.getFieldValue('someOtherField') == null,
    ...
  })}
  // or maybe expose values directly like form.Subscribe
  meta={({ values }) => ({
    disabled: values.someOtherField == null,
    ...
  })}
>
  {(field, meta) => <Comp
    disabled={meta.disabled}
    ... 

[crutchcorn]

These are actually really impressive API ideas. Can you make GH issues for each of them and we can discuss each with their own merits?

[ha1fstack]

For sure, thanks! I might also create PR draft for this feature 😀