X-Git-Url: http://nitlanguage.org?ds=sidebyside

diff --git a/lib/serialization/caching.nit b/lib/serialization/caching.nit
index d32a0c2..4541428 100644
--- a/lib/serialization/caching.nit
+++ b/lib/serialization/caching.nit
@@ -24,6 +24,21 @@ abstract class CachingSerializer
 
 	# Cache of known objects
 	var cache = new SerializerCache is lazy, writable
+
+	# Link the cache of `self` with `deserializer`
+	#
+	# This allows reference objects by id when they are known by the other side
+	# of the stream.
+	#
+	# Use `cache` if it is a `DuplexCache`, otherwise create a new one.
+	fun link(deserializer: CachingDeserializer)
+	do
+		var mem = self.cache
+		if not mem isa DuplexCache then mem = new DuplexCache
+
+		self.cache = mem
+		deserializer.cache = mem
+	end
 end
 
 # A `Deserializer` with a `cache`
@@ -59,10 +74,13 @@ class SerializerCache
 	# Require: `not has_object(object)`
 	fun new_id_for(object: Serializable): Int
 	do
-		var id = sent.length
+		var id = next_available_id
 		sent[object] = id
 		return id
 	end
+
+	# Get a free id to associate to an object in the cache
+	protected fun next_available_id: Int do return sent.length
 end
 
 # Cache of received objects sorted by there reference id
@@ -81,3 +99,39 @@ class DeserializerCache
 	# Associate `object` to `id`
 	fun []=(id: Int, object: Object) do received[id] = object
 end
+
+# A shared cache for serialization and deserialization
+class DuplexCache
+	super SerializerCache
+	super DeserializerCache
+
+	redef fun new_id_for(object)
+	do
+		var id = super
+		received[id] = object
+		return id
+	end
+
+	redef fun []=(id, object)
+	do
+		super
+		assert object isa Serializable
+		sent[object] = id
+	end
+end
+
+# A shared cache where 2 clients serialize objects at the same types, prevents references collision
+class AsyncCache
+	super DuplexCache
+
+	# Should this end use even numbers?
+	var use_even: Bool
+
+	private var last_id: Int is lazy do return if use_even then 0 else 1
+
+	redef fun next_available_id
+	do
+		last_id += 2
+		return last_id
+	end
+end