tuned signature;

--- a/src/Pure/PIDE/text.scala	Wed Aug 25 22:57:40 2010 +0200
+++ b/src/Pure/PIDE/text.scala	Thu Aug 26 11:29:43 2010 +0200
@@ -33,7 +33,7 @@
     def +(i: Offset): Range = map(_ + i)
     def -(i: Offset): Range = map(_ - i)
 
-    def is_singleton: Boolean = start == stop
+    def is_singularity: Boolean = start == stop
 
     def contains(i: Offset): Boolean = start == i || start < i && i < stop
     def contains(that: Range): Boolean = this.contains(that.start) && that.stop <= this.stop