--- a/mercurial/help/revsets.txt	Sat Apr 30 10:57:13 2011 -0500
+++ b/mercurial/help/revsets.txt	Sat Apr 30 17:43:04 2011 +0200
@@ -42,6 +42,20 @@
 
 ``x - y``
   Changesets in x but not in y.
+  
+``x^n``
+  The nth parent of x, n == 0, 1, or 2.
+  For n == 0, x; for n == 1, the first parent of each changeset in x;
+  for n == 2, the second parent of changeset in x.
+
+``x~n``
+  The nth first ancestor of x; ``x~0`` is x; ``x~3`` is ``x^^^``.
+
+There is a single postfix operator:
+
+``x^``
+  Equivalent to ``x^1``, the first parent of each changeset in x.
+
 
 The following predicates are supported: