Factor out undo-demo into its own namespace

demo/reagentdemo/news.cljs

@@ -1,95 +1,12 @@
 (ns reagentdemo.news
   (:require [reagent.core :as reagent :refer [atom]]
             [reagent.debug :refer-macros [dbg println]]
-            [reagentdemo.syntax :refer-macros [get-source]]
             [reagentdemo.page :refer [title link page-map]]
             [reagentdemo.common :as common :refer [demo-component]]
             [reagentdemo.news.async :as async]
-            [todomvc :as todomvc]))
-
-(def funmap (-> "reagentdemo/news.cljs" get-source common/fun-map))
-(def src-for (partial common/src-for funmap))
-
-(def state todomvc/todos)
-
-(def undo-list (atom nil))
-
-(defn undo []
-  (let [undos @undo-list]
-    (when-let [old (first undos)]
-      (reset! state old)
-      (reset! undo-list (rest undos)))))
-
-(defn undo-button []
-  (let [n (count @undo-list)]
-    [:input {:type "button" :on-click undo
-             :disabled (zero? n)
-             :value (str "Undo (" n ")")}]))
-
-(defn todomvc-with-undo []
-  (add-watch state ::undo-watcher
-             (fn [_ _ old-state _]
-               (swap! undo-list conj old-state)))
-  [:div
-   [undo-button]
-   [todomvc/todo-app]])
-
-(defn undo-demo []
-  [demo-component {:comp todomvc-with-undo
-                   :src (src-for [:state :undo-list :undo :save-state
-                                  :undo-button :todomvc-with-undo])}])
-
-(def undo-demo-cleanup
-  (with-meta undo-demo {:component-will-unmount
-                        (fn []
-                          (reset! undo-list nil)
-                          (remove-watch state ::undo-watcher))}))
-
-(defn undo-example [{:keys [summary]}]
-  (let [head "Cloact becomes Reagent: Undo is trivial"]
-    [:div.reagent-demo
-     [:h1 [link {:href undo-example} head]]
-     [title head]
-     [:div.demo-text
-      [:h2 "(reset! cloact-name \"Reagent\")"]
-
-      [:p "It turns out that ”Cloact” was a really, really bad
-      name. It made some people think about birds’ behinds, in
-      possibly unhealthy ways, which even Google suggested they
-      should."]
-
-      [:p "The new name is " [:strong "Reagent"] ", which hopefully
-      doesn’t bring with it the same disgusting connotations."]
-
-      [:p "The API is otherwise unchanged, so a simple
-      search-and-replace should suffice."]
-
-      (if summary
-        [link {:href undo-example
-               :class 'news-read-more} "Read more"]
-        [:div.demo-text
-
-         [:h2 "Undo the easy way"]
-
-         [:p "To celebrate the undoing of the apparently disgusting
-         name, here is an example of how easy it is to add undo
-         functionality to Reagent components."]
-
-         [:p "It simply saves the old state whenever it changes, and
-         restores it when the button is clicked."]
-
-         [:p "The really nice thing about ClojureScript is that not
-         only is this easy and safe to do, courtesy of immutable data
-         structures, it is also efficient. ClojureScript figures out
-         how to represent ”changes” to maps and vectors efficiently,
-         so that you won’t have to."]
-
-         [undo-demo-cleanup]])]]))
+            [reagentdemo.news.undo-demo :as undo-demo]))
 
 (defn main []
   [:div
    [async/main {:summary true}]
-   [undo-example {:summary true}]])
-
-(swap! page-map assoc
-       "news/cloact-reagent-undo-demo.html" undo-example)
+   [undo-demo/main {:summary true}]])

demo/reagentdemo/news/undo-demo.cljs

@@ -0,0 +1,89 @@
+(ns reagentdemo.news.undo-demo
+  (:require [reagent.core :as reagent :refer [atom]]
+            [reagent.debug :refer-macros [dbg println]]
+            [reagentdemo.syntax :refer-macros [get-source]]
+            [reagentdemo.page :refer [title link page-map]]
+            [reagentdemo.common :as common :refer [demo-component]]
+            [todomvc :as todomvc]))
+
+(def funmap (-> "reagentdemo/news/undo-demo.cljs" get-source common/fun-map))
+(def src-for (partial common/src-for funmap))
+
+(def state todomvc/todos)
+
+(def undo-list (atom nil))
+
+(defn undo []
+  (let [undos @undo-list]
+    (when-let [old (first undos)]
+      (reset! state old)
+      (reset! undo-list (rest undos)))))
+
+(defn undo-button []
+  (let [n (count @undo-list)]
+    [:input {:type "button" :on-click undo
+             :disabled (zero? n)
+             :value (str "Undo (" n ")")}]))
+
+(defn todomvc-with-undo []
+  (add-watch state ::undo-watcher
+             (fn [_ _ old-state _]
+               (swap! undo-list conj old-state)))
+  [:div
+   [undo-button]
+   [todomvc/todo-app]])
+
+(defn undo-demo []
+  [demo-component {:comp todomvc-with-undo
+                   :src (src-for [:state :undo-list :undo :save-state
+                                  :undo-button :todomvc-with-undo])}])
+
+(def undo-demo-cleanup
+  (with-meta undo-demo {:component-will-unmount
+                        (fn []
+                          (reset! undo-list nil)
+                          (remove-watch state ::undo-watcher))}))
+
+(defn main [{:keys [summary]}]
+  (let [head "Cloact becomes Reagent: Undo is trivial"]
+    [:div.reagent-demo
+     [:h1 [link {:href main} head]]
+     [title head]
+     [:div.demo-text
+      [:h2 "(reset! cloact-name \"Reagent\")"]
+
+      [:p "It turns out that ”Cloact” was a really, really bad
+      name. It made some people think about birds’ behinds, in
+      possibly unhealthy ways, which even Google suggested they
+      should."]
+
+      [:p "The new name is " [:strong "Reagent"] ", which hopefully
+      doesn’t bring with it the same disgusting connotations."]
+
+      [:p "The API is otherwise unchanged, so a simple
+      search-and-replace should suffice."]
+
+      (if summary
+        [link {:href main
+               :class 'news-read-more} "Read more"]
+        [:div.demo-text
+
+         [:h2 "Undo the easy way"]
+
+         [:p "To celebrate the undoing of the apparently disgusting
+         name, here is an example of how easy it is to add undo
+         functionality to Reagent components."]
+
+         [:p "It simply saves the old state whenever it changes, and
+         restores it when the button is clicked."]
+
+         [:p "The really nice thing about ClojureScript is that not
+         only is this easy and safe to do, courtesy of immutable data
+         structures, it is also efficient. ClojureScript figures out
+         how to represent ”changes” to maps and vectors efficiently,
+         so that you won’t have to."]
+
+         [undo-demo-cleanup]])]]))
+
+(swap! page-map assoc
+       "news/cloact-reagent-undo-demo.html" main)