diff -r b96cf915de75 -r 9a2c266f97c8 src/Pure/PIDE/document.scala
--- a/src/Pure/PIDE/document.scala	Mon Apr 03 12:49:13 2017 +0200
+++ b/src/Pure/PIDE/document.scala	Mon Apr 03 13:39:13 2017 +0200
@@ -98,6 +98,7 @@
     object Name
     {
       val empty = Name("")
+      def theory(theory: String): Name = Name(theory, "", theory)
 
       object Ordering extends scala.math.Ordering[Name]
       {