Sync And Race Across Array Elements

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• using { /Verse.org/Simulation }
  
  # ArrayRace will call the Function argument for each element in the Array and wait for only one of the async functions to complete, canceling all the rest.
  # A divide-and-conquer concurrency algorithm that divides an array into two and races between the two subarrays.
  # This is a recursive implementation, where the function calls itself to race between the divided arrays.
  # The base case (the condition to stop the recursion) is the array has only one element.
  # This is a generic implementation using parametric types, so you can provide your own type and your own async function as arguments.
  ArrayRace(Array:[]t, Function(Element:t)<suspends>:u where t:type, u:type)<suspends>:u=
      # If more than two elements in the array, then split the array in half,
      # and race between the subarrays recursively.
      if:
          Array.Length > 1
          Mid := Floor(Array.Length / 2)
          LeftArray := Array.Slice[0, Mid]
          RightArray := Array.Slice[Mid]
      then:
          race:
              ArrayRace(LeftArray, Function)
              ArrayRace(RightArray, Function)
      else if:
          First := Array[0]
      then:
          # Grab the only element in the array and call the async function with it as the argument.
          Function(First)
      else:
          # A race with no subtasks never completes, so sleep infinitely and call Err() because we shouldn't return a value here.
          Sleep(Inf)
          Err()