fn cast_keys_only<K: ArrowDictionaryKeyType>(
array: &DictionaryArray<K>,
to_index_type: &DataType,
cast_options: &CastOptions<'_>,
) -> Result<ArrayRef, ArrowError>fn cast_keys_only<K: ArrowDictionaryKeyType>(
array: &DictionaryArray<K>,
to_index_type: &DataType,
cast_options: &CastOptions<'_>,
) -> Result<ArrayRef, ArrowError>