Updated to use cabal-dev

.gitignore

@@ -1,3 +1,3 @@
-dist
-sessions.vim
 .*.sw*
+/cabal-dev
+/dist

doc/todo

@@ -0,0 +1,19 @@
+
+TODO
+====
+
+Improve the Containers module
+* Fields are just lenses; the functions in this module shouldn't directly access
+  anything, they should just create lenses
+* One type of lens should access a value in a map given a particular key, with a
+  default value to insert and access if the value is not found
+  * This is just a specialization of an accessor that provides a Maybe value
+
+Support records which have two variants with a common field by only generating
+a single field descriptor.
+
+Support underscore-based naming as well as camel case. Provide wrappers around
+a single underlying function which takes all the relevant parameters.
+
+Write tests.
+

src/Data/Record/StateFields.hs

@@ -61,7 +61,13 @@ idReaderField f =
   { askFieldM = asks $ getField f
   }
 
-infixl 9 //
+infixl 9 //, >/, </
+
+(>/) :: a -> IdField a b -> b
+(>/) = flip getField
+
+(</) :: a -> (IdField a b, b) -> a
+(</) rec (f, val) = putField f val rec
 
 -- | The class of field descriptors which can be chained into paths.
 class FieldPath f g h | f g -> h where