From 590ab79493df03c951172f252f9675eeb9c724a3 Mon Sep 17 00:00:00 2001
From: Tim Watson <tim@rabbitmq.com>
Date: Fri, 15 Feb 2013 12:13:45 +0000
Subject: [PATCH] spike adding cpSendChan

---
 src/Control/Distributed/Process.hs            | 15 ++++++-----
 .../Process/Internal/Closure/BuiltIn.hs       | 25 +++++++++++++++++++
 2 files changed, 34 insertions(+), 6 deletions(-)

diff --git a/src/Control/Distributed/Process.hs b/src/Control/Distributed/Process.hs
index f2340e84..863ff5cf 100644
--- a/src/Control/Distributed/Process.hs
+++ b/src/Control/Distributed/Process.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE ScopedTypeVariables    #-}
+
 {- | [Cloud Haskell]
 
 This is an implementation of Cloud Haskell, as described in
@@ -179,6 +181,7 @@ import Control.Distributed.Process.Internal.Closure.BuiltIn
   , splitCP
   , cpLink
   , cpSend
+  , cpSendChan
   , cpNewChan
   , cpDelay
   )
@@ -421,14 +424,14 @@ spawnChannel :: forall a. Typeable a => Static (SerializableDict a)
              -> Closure (ReceivePort a -> Process ())
              -> Process (SendPort a)
 spawnChannel dict nid proc = do
-    us <- getSelfPid
-    _ <- spawn nid (go us)
-    expect
+    (sp, rp) <- newChan
+    _ <- spawn nid (go sp)
+    r <- receiveChan rp
   where
-    go :: ProcessId -> Closure (Process ())
-    go pid = cpNewChan dict
+    go :: SendPort (SendPort a) -> Closure (Process ())
+    go chan = cpNewChan dict
            `bindCP`
-             (cpSend (sdictSendPort dict) pid `splitCP` proc)
+             (cpSendChan (sdictSendPort dict) chan `splitCP` proc)
            `bindCP`
              (idCP `closureCompose` staticClosure sndStatic)
 
diff --git a/src/Control/Distributed/Process/Internal/Closure/BuiltIn.hs b/src/Control/Distributed/Process/Internal/Closure/BuiltIn.hs
index 763c9d07..08b829d9 100644
--- a/src/Control/Distributed/Process/Internal/Closure/BuiltIn.hs
+++ b/src/Control/Distributed/Process/Internal/Closure/BuiltIn.hs
@@ -19,6 +19,7 @@ module Control.Distributed.Process.Internal.Closure.BuiltIn
   , cpLink
   , cpUnlink
   , cpSend
+  , cpSendChan
   , cpExpect
   , cpNewChan
     -- * Support for some CH operations
@@ -59,6 +60,7 @@ import Control.Distributed.Process.Internal.Primitives
   , send
   , expect
   , newChan
+  , sendChan
   , monitor
   , unmonitor
   , match
@@ -83,6 +85,7 @@ remoteTable =
     . registerStatic "$link"            (toDynamic link)
     . registerStatic "$unlink"          (toDynamic unlink)
     . registerStatic "$sendDict"        (toDynamic (sendDict         :: SerializableDict ANY -> ProcessId -> ANY -> Process ()))
+    . registerStatic "$sendChanDict"    (toDynamic (sendChanDict     :: SerializableDict ANY -> (SendPort ANY) -> ANY -> Process ()))
     . registerStatic "$expectDict"      (toDynamic (expectDict       :: SerializableDict ANY -> Process ANY))
     . registerStatic "$newChanDict"     (toDynamic (newChanDict      :: SerializableDict ANY -> Process (SendPort ANY, ReceivePort ANY)))
     . registerStatic "$cpSplit"         (toDynamic (cpSplit          :: (ANY1 -> Process ANY3) -> (ANY2 -> Process ANY4) -> (ANY1, ANY2) -> Process (ANY3, ANY4)))
@@ -98,6 +101,12 @@ remoteTable =
     sendDict :: forall a. SerializableDict a -> ProcessId -> a -> Process ()
     sendDict SerializableDict = send
 
+    sendChanDict :: forall a . SerializableDict a
+                 -> SendPort a
+                 -> a
+                 -> Process ()
+    sendChanDict SerializableDict = sendChan
+
     expectDict :: forall a. SerializableDict a -> Process a
     expectDict SerializableDict = expect
 
@@ -201,6 +210,9 @@ bindCP x f = bindProcessStatic `closureApplyStatic` x `closureApply` f
 decodeProcessIdStatic :: Static (ByteString -> ProcessId)
 decodeProcessIdStatic = staticLabel "$decodeProcessId"
 
+decodeSendPortStatic :: forall a . Typeable a => Static (ByteString -> SendPort a)
+decodeSendPortStatic = staticLabel "$sdictSendPort_"
+
 -- | 'CP' version of 'link'
 cpLink :: ProcessId -> Closure (Process ())
 cpLink = closure (linkStatic `staticCompose` decodeProcessIdStatic) . encode
@@ -229,6 +241,19 @@ cpSend dict pid = closure decoder (encode pid)
                    => Static (SerializableDict a -> ProcessId -> a -> Process ())
     sendDictStatic = staticLabel "$sendDict"
 
+cpSendChan :: forall a. Typeable a
+           => Static (SerializableDict a) -> SendPort a -> CP a ()
+cpSendChan dict sp = closure decoder (encode sp)
+  where
+    decoder :: Static (ByteString -> a -> Process ())
+    decoder = (sendChanDictStatic `staticApply` dict)
+              `staticCompose`
+              decodeSendPortStatic
+
+    sendChanDictStatic :: Typeable a
+                       => Static (SerializableDict a -> SendPort a -> a -> Process ())
+    sendChanDictStatic = staticLabel "$sendChanDict"
+
 -- | 'CP' version of 'expect'
 cpExpect :: Typeable a => Static (SerializableDict a) -> Closure (Process a)
 cpExpect dict = staticClosure (expectDictStatic `staticApply` dict)