diff --git a/src/GF/Grammar/PatternMatch.hs b/src/GF/Grammar/PatternMatch.hs
index cbf77063d..696f19e78 100644
--- a/src/GF/Grammar/PatternMatch.hs
+++ b/src/GF/Grammar/PatternMatch.hs
@@ -59,6 +59,7 @@ tryMatch (p,t) = do
       (PV IW, _) | isInConstantForm t -> return [] -- optimization with wildcard
       (PV x,  _) | isInConstantForm t -> return [(x,t)]
       (PString s, ([],K i,[])) | s==i -> return []
+      (PString "",([],Empty,[]))      -> return [] -- because "" = [""] = []
       (PInt s, ([],EInt i,[])) | s==i -> return []
       (PC p pp, ([], Con f, tt)) | 
             p `eqStrIdent` f && length pp == length tt ->