From 5609772cd3b43307d13a1b3a0d5f378fc31f816d Mon Sep 17 00:00:00 2001
From: Adam Tankanow <Adam.Tankanow@gmail.com>
Date: Fri, 9 Jan 2015 07:16:22 -0500
Subject: [PATCH] Add docstring and support for creating links for header id
 attributes

- this method will now look for both of the following references, this
  commit adds support for (2)

(1) <h1><a name="href">Reference Text</a></h1>
and
(2) <h1 id="href">Reference Text</h1>
---
 src/cryogen_core/toc.clj | 28 +++++++++++++++++++---------
 1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/src/cryogen_core/toc.clj b/src/cryogen_core/toc.clj
index a1021d5..871dba4 100644
--- a/src/cryogen_core/toc.clj
+++ b/src/cryogen_core/toc.clj
@@ -18,16 +18,26 @@
           headings)))
     [] content))
 
-(defn make-links [headings]
+(defn make-links
+  "Create a table of contents from the given headings. This function will look
+  for either:
+  (1) headings with a child anchor with a non-nil name attribute, e.g.
+      <h1><a name=\"reference\">Reference Title</a></h1>
+  or
+  (2) headings with an id attribute, e.g. <h1 id=\"reference\">Reference Title</h1>
+  In both cases above, the anchor reference becomes \"#reference\" and the
+  anchor text is \"Reference Title\"."
+  [headings]
   (loop [items headings acc nil _last nil]
-    (if-let [{tag :tag [{{name :name} :attrs} title] :content} (first items)]
-      (if (nil? name) (recur (rest items) acc nil)
-          (let [entry [:li [:a {:href (str "#" name)} title]]
-                jump (compare_index _last tag)]
-            (cond (> jump 0) (recur (rest items) (str acc "<ol>" (hiccup/html entry)) tag)
-                  (= jump 0) (recur (rest items) (str acc (hiccup/html entry)) tag)
-                  (< jump 0) (recur (rest items) (str acc (apply str (repeat (* -1 jump) "</ol>"))
-                                                      (hiccup/html entry)) tag))))
+    (if-let [{tag :tag {id :id} :attrs [{{name :name} :attrs} title :as htext] :content} (first items)]
+      (let [anchor (or id name)]
+        (if (nil? anchor) (recur (rest items) acc nil)
+            (let [entry [:li [:a {:href (str "#" anchor)} (or title (first htext))]]
+                  jump (compare_index _last tag)]
+              (cond (> jump 0) (recur (rest items) (str acc "<ol>" (hiccup/html entry)) tag)
+                    (= jump 0) (recur (rest items) (str acc (hiccup/html entry)) tag)
+                    (< jump 0) (recur (rest items) (str acc (apply str (repeat (* -1 jump) "</ol>"))
+                                                        (hiccup/html entry)) tag)))))
       (str acc "</ol>"))))
 
 (defn generate-toc [html]