RTNode constifies constant SigStreams

2 files changed, 25 insertions, 12 deletions

diff --git a/alv/base/input.moon b/alv/base/input.moon
index b73a476..f29bd10 100644
--- a/alv/base/input.moon
+++ b/alv/base/input.moon
@@ -76,8 +76,11 @@ class Input
   metatype: => @result.metatype
 
   --- the current value
-  --
-  -- @tfield SigStream result
+  -- @tfield Result result
+
+  --- the Input mode
+  -- @tfield string mode `'hot'`, `'cold'` or `'io'`.
+  mode: 'hot'
 
 --- members
 -- @section members
@@ -125,17 +128,25 @@ class Input
     InputType value
 
 class ColdInput extends Input
+  mode: 'cold'
   dirty: => false
 
 class ValueInput extends Input
-  setup: (old) => @dirty_setup = not old or @result != old.result
+  new: (result) =>
+    super result
+    @mode = if @result.metatype == '=' then 'cold' else 'hot'
+
+  setup: (old) =>
+    @dirty_setup = not old or @result != old.result
+
   finish_setup: => @dirty_setup = nil
+
   dirty: =>
     return @dirty_setup if @dirty_setup != nil
     @result\dirty!
 
 class IOInput extends Input
-  io: true
+  mode: 'io'
 
 mapping = {
   [Constant]: ValueInput
diff --git a/alv/rtnode.moon b/alv/rtnode.moon
index b10f9a1..23cffa5 100644
--- a/alv/rtnode.moon
+++ b/alv/rtnode.moon
@@ -45,7 +45,7 @@ class RTNode
   -- should be called once per frame on the root, right before tick.
   poll_io: =>
     for result, input in pairs @side_inputs
-      result\poll! if input.io
+      result\poll! if input.mode == 'io'
 
   --- in depth-first order, tick all Ops which have dirty Inputs.
   --
@@ -120,13 +120,15 @@ class RTNode
         is_child[child.result] = true
 
     if @op
-      for input in @op\all_inputs!
-        continue if input.result.metatype == '='
-        if input.io or not is_child[input.result]
-          @side_inputs[input.result] = input
-
-    if @result and @result.metatype == '='
-      assert not (next @side_inputs), "Const result has side_inputs"
+      for i in @op\all_inputs!
+        if i.mode == 'io' or (i.mode == 'hot' and not is_child[i.result])
+          @side_inputs[i.result] = i
+
+    if @result
+      if next @side_inputs
+        assert @result.metatype != '=', "Const result has side_inputs"
+      elseif @result.metatype == '~'
+        @result = @result.type\mk_const @result\unwrap!
 
 {
   :RTNode