X-Git-Url: http://git.cielonegro.org/gitweb.cgi?p=hs-rrdtool.git;a=blobdiff_plain;f=Data%2FHList%2FString.hs;fp=Data%2FHList%2FString.hs;h=6d4d52ddfeba32fbaaad0c5488027a8ce81c1bd1;hp=e3f878a25b69a8ecb82109dca957cc3c6d56c75a;hb=57b97113a93d366f14278a12b8170a1c06e258a1;hpb=a584a7c4d5ff7e6651f41070b0d2d5032d49b0dd

diff --git a/Data/HList/String.hs b/Data/HList/String.hs
index e3f878a..6d4d52d 100644
--- a/Data/HList/String.hs
+++ b/Data/HList/String.hs
@@ -11,11 +11,17 @@ import Types.Data.Num.Decimal.Literals.TH
 import Types.Data.Num.Ops
 
 
-class HString s
+class (Show s, Eq s) => HString s
 
 instance HString HNil
 
-instance IntegerT c => HString (HCons c s)
+instance ( Show c
+         , Show s
+         , Eq c
+         , Eq s
+         , IntegerT c
+         )
+    => HString (HCons c s)
 
 hString :: QuasiQuoter
 hString = QuasiQuoter quoteStrExp quoteStrPat