diff -r 1324268c2f6a -r ce09e947c1d5 src/Pure/PIDE/text.scala
--- a/src/Pure/PIDE/text.scala	Tue Apr 04 18:43:47 2017 +0200
+++ b/src/Pure/PIDE/text.scala	Tue Apr 04 18:43:58 2017 +0200
@@ -82,7 +82,7 @@
 
     def full: Perspective = Perspective(List(Range.full))
 
-    def apply(ranges: Seq[Range]): Perspective =
+    def apply(ranges: List[Range]): Perspective =
     {
       val result = new mutable.ListBuffer[Range]
       var last: Option[Range] = None