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kotlinlang

How can I use the `keepPreviousData` flag in React Query’s `useQuery` through `placeHolderData` ?
Through the kotlin-wrappers the former is defined as `external fun <T> keepPreviousData(previousData: T?): T?` and the latter as `Any`, with some types commented out. Library docs: <https://tanstack.com/query/v5/docs/react/guides/paginated-queries#better-paginated-queries-with-placeholderdata|Tanstack Query docs>

I’m using wrappers-bom:1.0.0-pre.668.

```placeholderData = ::keepPreviousData```

Nice, but how can I pass type parameter?
`Not enough information to infer type variable T`

That yields compilation errors `Expecting an identifier` and `Type arguments are not allowed`

I tried wrapping the generated function like this:
```fun wrapperFunc(previousData: GroupedResponse&lt;Show&gt;?):GroupedResponse&lt;Show&gt;? = keepPreviousData(previousData)```
and then doing
`placeholderData = ::wrapperFunc` .
This compiles, but does not yield the expected behaviour

I also tried following the options described <https://tanstack.com/query/latest/docs/react/guides/placeholder-query-data|here>, both through a val and a fun:
`
```val placeholderDataVal: (previousData: GroupedResponse&lt;Show&gt;?, previousQuery: Any?) -&gt; GroupedResponse&lt;Show&gt;? = { previousData, _ -&gt; previousData }

with
placeholderData = placeholderDataVal```
and
```    fun placeholderDataFunc(previousData:  GroupedResponse&lt;Show&gt;?, previousQuery: Any?):  GroupedResponse&lt;Show&gt;? = previousData

with
placeholderData = ::placeholderDataFunc```
. Same as above: Compiles but not obtaining desired functionality

Looks like <https://github.com/TanStack/query/issues|bug> :disappointed:

I’ll look into it, thank you for helping!

They have fine codesandbox templates in docs for fast test case creation.