Port page list module a bit

1 files changed, 53 insertions, 0 deletions

diff --git a/src/Hakyll/Web/Template/List.hs b/src/Hakyll/Web/Template/List.hs
new file mode 100644
index 0000000..e8da74f
--- /dev/null
+++ b/src/Hakyll/Web/Template/List.hs
@@ -0,0 +1,53 @@
+--------------------------------------------------------------------------------
+-- | Provides an easy way to combine several items in a list. The applications
+-- are obvious:
+--
+-- * A post list on a blog
+--
+-- * An image list in a gallery
+--
+-- * A sitemap
+module Hakyll.Web.Template.List
+    ( applyTemplateList
+    , chronological
+    , recentFirst
+    ) where
+
+
+--------------------------------------------------------------------------------
+import           Data.List                   (sortBy)
+import           Data.Ord                    (comparing)
+import           System.FilePath             (takeBaseName)
+
+
+--------------------------------------------------------------------------------
+import           Hakyll.Core.Compiler
+import           Hakyll.Core.Identifier
+import           Hakyll.Core.Item
+import           Hakyll.Web.Template
+import           Hakyll.Web.Template.Context
+
+
+--------------------------------------------------------------------------------
+-- | Set a field of a page to a listing of pages
+applyTemplateList :: Template
+                  -> Context a
+                  -> [Item a]
+                  -> Compiler String
+applyTemplateList tpl context items = do
+    items' <- mapM (applyTemplate tpl context) items
+    return $ concat $ map itemBody items'
+
+
+--------------------------------------------------------------------------------
+-- | Sort pages chronologically. This function assumes that the pages have a
+-- @year-month-day-title.extension@ naming scheme -- as is the convention in
+-- Hakyll.
+chronological :: [Item a] -> [Item a]
+chronological = sortBy $ comparing $ takeBaseName . toFilePath . itemIdentifier
+
+
+--------------------------------------------------------------------------------
+-- | The reverse of 'chronological'
+recentFirst :: [Item a] -> [Item a]
+recentFirst = reverse . chronological