csys: clean-up, use comprehensions instead of reduce; + synapse operation: multiply

lib/csys/csys.ex

@@ -29,7 +29,8 @@ defmodule Scopes.CSys do
   end
 
   def forward(msg, scope) do
-    Enum.reduce(syns(scope), false, fn s, _acc -> s.(msg); true end)
+    for s <- syns(scope), reduce: false, do: (_acc -> s.(msg))
+    #Enum.reduce(syns(scope), false, fn s, _acc -> s.(msg); true end)
   end
 
   def create(_msg, scope = {state, proc, _syns, env}) do
@@ -40,15 +41,13 @@ defmodule Scopes.CSys do
 
   def connect(msg, {state, proc, syns, env}) do
     data = Shape.data(msg)
-    op = data[:op] || noop()
+    op = data[:op] || []
     syn = synapse(data[:target], op, 0)
     update({state, proc, [syn | syns], env})
   end
 
 # synapse operations
   
-  def noop(), do: fn msg -> msg end
-
   def filter_head(pat) do
     fn msg -> if List.starts_with?(Shape.head(msg), pat), do: msg end
   end
@@ -83,13 +82,11 @@ defmodule Scopes.CSys do
   # helpers
 
   def compose(ops) do
-    fn msg -> Enum.reduce(ops, msg, &bind/2) end
-  end
-
-  defp bind(op, val) do
-    case val do
-      nil -> nil
-      val -> op.(val)
+    fn msg -> 
+      for op <- ops, reduce: msg do
+        nil -> nil
+        val -> op.(val)
+      end
     end
   end
 end

lib/csys/program.ex

@@ -4,13 +4,14 @@ alias Scopes.CSys
   alias Scopes.Shape
 
   defmodule State do
-    defstruct [:value, :threshold, :stage, :prog]
+    defstruct [:value, :threshold, :bias, :stage, :prog]
   end
 
   def prepare(prog, args) do
     state = %State{
-      value: args[:value], 
+      value: args[:bias], 
       threshold: args[:threshold], 
+      bias: args[:bias], 
       stage: :initial, 
       prog: prog
     }
@@ -43,7 +44,7 @@ alias Scopes.CSys
     {stages, transitions}
   end
 
-  def prepare_basic(args \\ [value: 0, threshold: 0]) do
+  def prepare_basic(args \\ [threshold: 0, bias: 0]) do
     prepare(basic_prog(), args)
   end
 
@@ -80,7 +81,7 @@ alias Scopes.CSys
     if value_n >= state.threshold do
       msg = Shape.create(Shape.head(msg), data: %{data | value: value_n})
       CSys.forward(msg, scope) || CSys.notify(msg, scope)
-      state_n = %{state | value: 0}
+      state_n = %{state | value: state.bias}
       CSys.update(put_elem(scope, 0, state_n))
     else
       state_n = %{state | value: value_n}
@@ -93,7 +94,8 @@ alias Scopes.CSys
     state = CSys.state(scope)
     value = data[:value] || state.value
     threshold = data[:threshold] || state.threshold
-    state_n = %{state | value: value, threshold: threshold}
+    bias = data[:bias] || state.bias
+    state_n = %{state | value: value, threshold: threshold, bias: bias}
     CSys.update(put_elem(scope, 0, state_n))
   end
 
@@ -111,13 +113,15 @@ alias Scopes.CSys
 
 # synapse operations
 
-  def negate() do
+  def multiply(n) do
     fn msg ->
       value = Shape.data(msg)[:value] || 0
-      Shape.create(Shape.head(msg), data: %{Shape.data(msg) | value: -value})
+      Shape.create(Shape.head(msg), data: %{Shape.data(msg) | value: n * value})
     end
   end
 
+  def negate(), do: multiply(-1)
+
 # helper functions
 
   def restart({state, _proc, syns, env}) do

test/csys_test.exs

@@ -16,17 +16,12 @@ defmodule Scopes.CSysTest do
     Shape.data(receive_select(head))
   end
 
-  def neg_only() do
-    fn msg -> if Shape.data(msg)[:value] < 0, do: msg end
-  end
-
   describe "basic:" do
     test "minimal-neural-net" do
       _env = Environ.setup(Program.prepare_basic())
       zero = receive_data([:csys, :created]).new
       CSys.send_value(zero, 0)
       assert 0 = receive_data().value
-      #CSys.send_message(zero, [:csys, :create, :pred], %{op: neg_only()})
       CSys.send_message(zero, [:csys, :create, :pred], 
         %{op: [CSys.data_only(), Program.negate()]})
       one = receive_data([:csys, :created]).new
@@ -34,7 +29,7 @@ defmodule Scopes.CSysTest do
       two = receive_data([:csys, :created]).new
       Process.sleep(1)
       CSys.send_value(one, 1)
-      assert receive_data().value in [-1, 1]
+      assert receive_data().value == 1
       #assert receive_data().value in [-1, 1]
       CSys.send_message(two, [:csys, :create, :pred])
       three = receive_data([:csys, :created]).new