Function formStateHasField

formStateHasField<
    FV extends FormValues,
    F extends string | number | symbol,
    TF extends string | number | symbol,
>(
    formState: Pick<FormState<Pick<FV, F>>, "formValues">,
    fieldName: TF,
): formState is FormState<Pick<FV, F | TF>>
Type guard to check whether the form values (of a type constructed from another with Pick and a parameterized key type) for the given form state contain the given field name. In other words, reports whether F extends TF.
Type Parameters
- FV extends FormValues
- F extends string | number | symbol
- TF extends string | number | symbol
Parameters
- formState: Pick<FormState<Pick<FV, F>>, "formValues">
  The form state to check.
- fieldName: TF
  The field name to check for.
Returns formState is FormState<Pick<FV, F | TF>>
Example
```
function setFields<K extends keyof ExampleFormValues = keyof ExampleFormValues>(formState: FormState<Pick<ExampleFormValues, K>>) {
	if (formStateHasField(formState, "name")) {
		formState.formSetFunctions.name("New Name");
	}
}
```