Set example language field for correct highlighting

Author: david-christiansen

message-index/site.hs

@@ -76,6 +76,11 @@ main = hakyll $ do
                   ( mconcat
                       [ urlField "url",
                         field "name" (pure . view _1 . itemBody),
+                        -- Set the language that highlight.js should use for syntax highlighting
+                        field "language" $ \(itemBody -> (filename, _, _)) ->
+                          pure $ case dropWhile (== '.') $ takeExtension filename of
+                            "hs" -> "haskell"
+                            other -> other,
                         field "before" (maybe (pure "<not present>") (fmap itemBody . load . itemIdentifier) . view _2 . itemBody),
                         field "after" (maybe (pure "<not present>") (fmap itemBody . load . itemIdentifier) . view _3 . itemBody)
                       ]
@@ -193,10 +198,14 @@ getExampleFiles = do
     ["messages", id, exampleName, _mdFile] -> pure (id, exampleName)
     _ -> fail "Not processing an example"
 
-  let beforePattern = foldl1 (.||.) $ exampleExtensions <&> \ext ->
-        fromGlob ("messages/" <> id <> "/" <> exampleName <> "/before/*." <> ext)
-      afterPattern = foldl1 (.||.) $ exampleExtensions <&> \ext ->
-        fromGlob ("messages/" <> id <> "/" <> exampleName <> "/after/*." <> ext)
+  let beforePattern =
+        foldl1 (.||.) $
+          exampleExtensions <&> \ext ->
+            fromGlob ("messages/" <> id <> "/" <> exampleName <> "/before/*." <> ext)
+      afterPattern =
+        foldl1 (.||.) $
+          exampleExtensions <&> \ext ->
+            fromGlob ("messages/" <> id <> "/" <> exampleName <> "/after/*." <> ext)
 
   before <- loadAll (beforePattern .&&. hasVersion "raw")
   after <- loadAll (afterPattern .&&. hasVersion "raw")

message-index/templates/example.html

@@ -6,14 +6,14 @@
     <div class="example-inner">
       <div class="example-title">Before</div>
       <!-- keep next line as is, i.e., on one line, or the code will not format properly -->
-      <pre class="example-pre"><code class="language-haskell">$before$</code></pre>
+      <pre class="example-pre"><code class="language-$language$">$before$</code></pre>
     </div>
   </div>
   <div class="example">
     <div class="example-inner">
       <div class="example-title">After</div>
       <!-- keep next line as is, i.e., on one line, or the code will not format propertly -->
-      <pre class="example-pre"><code class="language-haskell">$after$</code></pre>
+      <pre class="example-pre"><code class="language-$language$">$after$</code></pre>
     </div>
   </div>
 </div>