@@ -112,7 +112,11 @@ data D = Text Int String
112112 deriving (Show, Eq)
113113
114114newtype Doc = Doc { unDoc :: Seq D }
115+#if MIN_VERSION_base(4,9,0)
116+ deriving (Semigroup, Monoid, Show, Eq)
117+#else
115118 deriving (Monoid, Show, Eq)
119+#endif
116120
117121instance IsString Doc where
118122 fromString = text