X-Git-Url: http://nitlanguage.org

diff --git a/lib/poset.nit b/lib/poset.nit
index a5425dd..93afcf1 100644
--- a/lib/poset.nit
+++ b/lib/poset.nit
@@ -71,7 +71,7 @@ module poset
 #
 # Thanks to the `[]` method, elements can be considered relatively to the poset.
 # SEE `POSetElement`
-class POSet[E: Object]
+class POSet[E]
 	super Collection[E]
 	super Comparator
 
@@ -228,7 +228,7 @@ class POSet[E: Object]
 	#
 	# Nodes are labeled with their `to_s` so homonymous nodes may appear.
 	# Edges are unlabeled.
-	fun write_dot(f: OStream)
+	fun write_dot(f: Writer)
 	do
 		f.write "digraph \{\n"
 		var ids = new HashMap[E, Int]
@@ -258,7 +258,7 @@ class POSet[E: Object]
 	# See `write_dot` for details.
 	fun show_dot
 	do
-		var f = new OProcess("dot", "-Txlib")
+		var f = new ProcessWriter("dot", "-Txlib")
 		write_dot(f)
 		f.close
 		f.wait
@@ -379,7 +379,7 @@ end
 # # ...
 # t.in_some_relation.greaters
 # ~~~
-class POSetElement[E: Object]
+class POSetElement[E]
 	# The poset self belong to
 	var poset: POSet[E]