Add channel size to json serialization

1 files changed, 3 insertions, 1 deletions

diff --git a/Com/Simatime/Go.hs b/Com/Simatime/Go.hs
index e622539..f19511f 100644
--- a/Com/Simatime/Go.hs
+++ b/Com/Simatime/Go.hs
@@ -27,6 +27,7 @@ import qualified Control.Concurrent            as Concurrent
 import qualified Control.Concurrent.Chan.Unagi.Bounded
                                                as Chan
 import qualified Data.Aeson                    as Aeson
+import qualified System.IO.Unsafe              as Unsafe
 
 -- | A standard channel.
 data Channel a = Channel
@@ -36,7 +37,8 @@ data Channel a = Channel
   }
 
 instance Aeson.ToJSON (Channel a) where
-  toJSON _ = Aeson.String ("#<channel>" :: Text)
+  toJSON c = Aeson.String ("#<channel " <> len c <> ">" :: Text)
+    where len = show . Unsafe.unsafePerformIO . Chan.estimatedLength . _in
 
 -- | Starts a background process.
 fork :: IO () -> IO Concurrent.ThreadId