From: Tara L Andrews <tla@mit.edu>
Date: Fri, 3 Feb 2012 20:45:32 +0000 (+0100)
Subject: zap undefined value warning
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=84d4ca783d20c1606c29cc83e1c41c09ddd888f2;p=scpubgit%2Fstemmatology.git

zap undefined value warning
---

diff --git a/lib/Text/Tradition/Collation/RelationshipStore.pm b/lib/Text/Tradition/Collation/RelationshipStore.pm
index 93c4699..a74c890 100644
--- a/lib/Text/Tradition/Collation/RelationshipStore.pm
+++ b/lib/Text/Tradition/Collation/RelationshipStore.pm
@@ -259,7 +259,9 @@ sub relationship_valid {
 		# Check that linking the source and target in a relationship won't lead
 		# to a path loop for any witness.  If they have the same rank then fine.
 		return( 1, "ok" ) 
-			if $c->reading( $source )->rank == $c->reading( $target )->rank;
+			if $c->reading( $source )->has_rank
+				&& $c->reading( $target )->has_rank
+				&& $c->reading( $source )->rank == $c->reading( $target )->rank;
 		
 		# Otherwise, first make a lookup table of all the
 		# readings related to either the source or the target.