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Random quick question I hope, is it possible to run a task with a .submit and .map at the same time

like

```foo.submit(1)
foo.map([2, 3])```
?

That doesn’t really make sense. What are you trying to do?

So I'm trying to run a mapped task and not have tasks after it wait for the mapped task to finishing mapping before they start, I'll put some code up in a bit.

`cta_load_list : PrefectFuture = get_security_master_staging_cta_load_list.submit()`
    `cta_load_results = run_stored_procedure.map(`
        `sql_util=unmapped(staging_sql_util), procedure_name=cta_load_list`
    `)`
`security_master_side_load_list: PrefectFuture = (`
       `get_security_master_staging_dw_side_load_list.submit()`
`side_load_results = run_stored_procedure.map(`
        `sql_util=unmapped(dw_sql_util), procedure_name=security_master_side_load_list`
    `)`

So the 3rd list of get_security_master_side_load_list doesn't start until the mapping has finished mapping out. Would it be better if I put a waitfor on the 3rd line?

Mapping requires us to resolve the length of the input future in order to return the full list of mapped futures

Ok, I think I get it. So a map is basically the same as a submit, but there's like a couple of milliseconds/seconds after the map before the next task on the list can start?

Thanks for going through this with me by the way, these are the types of questions I am getting when trying to introduce this to the company, which usually uses C# for this sort of thing.

:+1: map does a submit behind the scenes for each item in the iterable(s) it receives

It’s equivalent to

```for i in items:
   task.submit(i)

# same as task.map(items)```

If `items` is a future we need to resolve the future to data (wait for it to complete) first so we can make those submissions

Gotcha, makes a lot of sense to me, thanks!