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Hi - Is `apply_map` the only way to implement a mapped case statement? Thanks

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I am running into an issue in `apply_map` where a task returns a list but the downstream task is not mapping over the list.  Is that expected behavior?

In the diagram I am referring to the bottom most task.

Hi <@UNSQ0T2V9> - Can you let us know where you're calling apply_map?  Or share your code for this?  I'm guessing you've already looked at these but the docs have a bit more about the different types of mapping: <https://docs.prefect.io/core/concepts/mapping.html#prefect-approach>

Hi <@ULXMV9SD7> - I am calling `apply_map` from the `add_new_vertex` the root task in the diagram.  The input for task `new_term_to_make` is a dictionary. When I run this code outside `apply_map` , in a flow it runs fine.

```with case(vertices_to_add.not_(), False):

        # getRecdoc = GetItem("resource-doc")
        # resource_doc = getRecdoc(first_vert_artifacts, 'resource_doc')
        
        # 1. Extract keyterms
        getKeyTerms = GetKeyterms(name="get-rec-keyterms")
        keyterm_df_lst = getKeyTerms(
            summary_dict=vertices_to_add["vertex"],
            resource_doc = vertices_to_add["resource_doc"]
        )
 

        # 2. Generate list of new nodes to make
        with tags("node-input-list"):
            terms_to_make_lst = genKeys.map(
                keyterm_df=keyterm_df_lst,
                resource_doc=unmapped(vertices_to_add["resource_doc"]),
                summary_dict=unmapped(vertices_to_add["vertex"]),
                # vertices_to_add=vertices_to_add,
                task_args={"name": "new-terms-to-make"}
            )```
This is the code outside *without* `apply_map`  The code inside `apply_map` is the same but with `unmapped` removed.

Hi itay, can you provide a reproducible example (<https://blog.dask.org/2018/02/28/minimal-bug-reports>) of the issue you're running into? Case statements in general should be usable inside apply_map, so if that's not working we'd need something reproducible to help debug further.

Yes. I will.  The `case` statement is working .  I expected one of the terminal task's to be mapped over the inputs...

Hi <@U011EKN35PT> - I asked the question in git.  Not as an issue  - It's probably just a lack of knowledge on my end.
<https://github.com/PrefectHQ/prefect/discussions/3287>