Changes between Version 6 and Version 7 of OverloadedLists

Timestamp:

11/10/12 02:52:07 (7 months ago)

Author:

giorgidze

Comment:

--

OverloadedLists

@@ -116 +116 @@
 
 One way to overload list patterns is to replace the {{{FromList}}} class from
-the previous section with the {{{ListRep}}} class defined as follows:
-
-{{{
-class ListRep l where
+the previous section with the {{{IsList}}} class defined as follows:
+
+{{{
+class IsList l where
   type Item l
   fromList  :: [Item l] -> l
@@ -149 +149 @@
 expressions and patterns. In other words, {{{:}}} is not overloaded.
 
-The instances of the {{{ListRep}}} class should satisfy the following
+The instances of the {{{IsList}}} class should satisfy the following
 property:
 
@@ -157 +157 @@
 
 The example {{{FromList}}} instances from the previous section can be extended
-into the {{{ListRep}}} instances as follows:
-
-{{{
-instance ListRep [a] where
+into the {{{IsList}}} instances as follows:
+
+{{{
+instance IsList [a] where
   type Item [a] = a
   fromList = id
   toList = id
 
-instance (Ord a) => ListRep (Set a) where
+instance (Ord a) => IsList (Set a) where
   type Item (Set a) = a
   fromList = Set.fromList
   toList = Set.toList
 
-instance (Ord k) => ListRep (Map k v) where
+instance (Ord k) => IsList (Map k v) where
   type Item (Map k v) = (k,v)
   fromList = Map.fromList
   toList = Map.toList
 
-instance ListRep (IntMap v) where
+instance IsList (IntMap v) where
   type Item (IntMap v) = (Int,v)
   fromList = IntMap.fromList
   toList = IntMap.toList
 
-instance ListRep Text where
+instance IsList Text where
   type Item Text = Char
   fromList = Text.pack
   toList = Text.unpack
 
-instance ListRep (Vector a) where
+instance IsList (Vector a) where
   type Item (Vector a) = a
   fromList  = Vector.fromList
@@ -191 +191 @@
   toList = Vector.toList
 }}}
+
+An alternative name for the {{{IsList}}} class could be {{{ListRep}}} (meaning
+representable as list). This is to emphasise that its instances should be
+representable as lists, it is not required for them to be lists.
 
 == Further GHC improvements/extensions that may benefit {{{OverloadedLists}}} ==