2016 Update

Task/Generator-Exponential/Elixir/generator-exponential.elixir

@@ -0,0 +1,47 @@
+defmodule Generator do
+  def filter( source_pid, remove_pid ) do
+    first_remove = next( remove_pid )
+    spawn( fn -> filter_loop(source_pid, remove_pid, first_remove) end )
+  end
+
+  def next( pid ) do
+    send(pid, {:next, self})
+    receive do
+      x -> x
+    end
+  end
+
+  def power( m ), do: spawn( fn -> power_loop(m, 0) end )
+
+  def task do
+    squares_pid = power( 2 )
+    cubes_pid = power( 3 )
+    filter_pid = filter( squares_pid, cubes_pid )
+    for _x <- 1..20, do: next(filter_pid)
+    for _x <- 1..10, do: next(filter_pid)
+  end
+
+  defp filter_loop( pid1, pid2, n2 ) do
+    receive do
+      {:next, pid} ->
+        {n, new_n2} = filter_loop_next( next(pid1), n2, pid1, pid2 )
+        send( pid, n )
+        filter_loop( pid1, pid2, new_n2 )
+    end
+  end
+
+  defp filter_loop_next( n1, n2, pid1, pid2 ) when n1 > n2, do:
+       filter_loop_next( n1, next(pid2), pid1, pid2 )
+  defp filter_loop_next( n, n, pid1, pid2 ), do:
+       filter_loop_next( next(pid1), next(pid2), pid1, pid2 )
+  defp filter_loop_next( n1, n2, _pid1, _pid2 ), do: {n1, n2}
+
+  defp power_loop( m, n ) do
+    receive do
+      {:next, pid} -> send( pid, round(:math.pow(n, m) ) )
+    end
+    power_loop( m, n + 1 )
+  end
+end
+
+IO.inspect Generator.task