return parser
longhelp="""
-Uses the RCS to compare the current tree with a previous tree, and prints
-a pretty report. If specifier is given, it is a specifier for the particular
-previous tree to use. Specifiers are specific to their RCS.
+Uses the RCS to compare the current tree with a previous tree, and
+prints a pretty report. If REVISION is given, it is a specifier for
+the particular previous tree to use. Specifiers are specific to their
+RCS.
For Arch your specifier must be a fully-qualified revision name.