diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/Accessor.hs | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/src/Accessor.hs b/src/Accessor.hs index a1623fc..ace78eb 100644 --- a/src/Accessor.hs +++ b/src/Accessor.hs @@ -15,7 +15,7 @@ module Accessor ) where -type Accessor s a r = (a -> a) -> s -> (s, r) +type Accessor s w r = (w -> w) -> s -> (s, r) accessor :: (s -> a) -> (a -> s -> s) -> Accessor s a a accessor getter setter f x = (setter newVal x, getter x) where @@ -33,7 +33,7 @@ set acc x = over acc (const x) infixr # (#) :: - Accessor obj middle middle -> Accessor middle end end -> Accessor obj end end + Accessor s1 a1 a1 -> Accessor a1 w2 r -> Accessor s1 w2 r (#) = composeAccessors where composeAccessors ac1 ac2 modifier obj = (newObj, value) @@ -92,3 +92,4 @@ sndAcc :: Accessor (a, b) b b sndAcc = accessor getter setter where getter (_, b) = b setter n x = (fst x, n) + |