Add AsEmpty
commit981ee3caa212bbd43babeaa14f2006fa6e49b7af
authorBen Gamari <bgamari.foss@gmail.com>
dateTue 20 Jan 2015, 11:41 (12 years ago)
parent48194c9
src/Data/Map/Monoidal.hs+4
@@ -52,6 +52,10 @@ instance Ord k => Ixed (MonoidalMap k a) where
5252
5353instance Each (MonoidalMap k a) (MonoidalMap k b) a b
5454
55+instance AsEmpty (MonoidalMap k a) where
56+ _Empty = nearly (MM M.empty) (M.null . unpack)
57+ {-# INLINE _Empty #-}
58+
5559instance Wrapped (MonoidalMap k a) where
5660 type Unwrapped (MonoidalMap k a) = M.Map k a
5761 _Wrapped' = iso unpack pack