Just tried it out. Async blocks evaluate to Task objects which have a wait method and a result attribute which evaluates to the value of the block.

    require 'async'
   
    res = Async do |task|
     name_task = task.async do 
       sleep 2
       "Jenny"
     end

    task.async do
      sleep 5
      9
    end

    "Hello #{name_task.wait}"
   end

   puts res  # => "Hello Jenny" after 5 seconds.

After using Python's and JS's async implementations this seems beautiful by comparison. Here's the a rough Python equivalent.

    import asyncio


    async def get_name():
        await asyncio.sleep(2)
        return "Jenny"


    async def get_number():
        await asyncio.sleep(5)
        return 7


    async def main():
        number_task = get_number()
        name_task = get_name()

        name, _ = await asyncio.gather(name_task, number_task)

        return f"Hello {name}"


    print(asyncio.run(main()))