Add news about next-tick and after-update

CHANGELOG.md

@@ -21,6 +21,10 @@
 
 - `cursor` now shares state between all instances corresponding to a given set of parameters.
 
+- `next-tick` now evokes its argument function at a clearly defined time (immediately before rendering, which is in turn triggered using requestAnimationFrame).
+
+- `after-update` is a new function, similar to `next-tick`, except that the function is evoked immediately after rendering.
+
 - Support `[:> nativeComp {:foo "bar"}]`
 
 - Reagent now falls back to using `require` if global `React` is undefined, to simplify use with e.g webpack and node.js.

demo/reagentdemo/news/news060.cljs

@@ -321,6 +321,18 @@
         that unnecessary re-renderings were avoided) when passed as
         arguments to child components."]]
 
+       [:section.demo-text
+        [:h2 "Tapping into the rendering loop"]
+
+        [:p [:code "next-tick"]" is an existing function, that now has
+        a more predictable timing. It takes a function that is invoked
+        immediately before the next rendering (which is in turn
+        triggered using "[:code "requestAnimationFrame"]")."]
+
+        [:p [:code "after-update"]" works just
+        like "[:code "next-tick"]", except that the function given is
+        invoked immediately "[:b "after"]" the next rendering."]]
+
        [:section.demo-text
         [:h2 "Breaking changes"]
 
@@ -338,13 +350,13 @@
          function, "[:code "reagent.ratom/reaction"]", "[:code "reagent.ratom/run!"]"
          and "[:code "reagent.ratom/make-reaction"]" are now lazy and
          executed asynchronously. Previously, reactions used to
-         execute directly whenever the atoms they depended on changed.
+         execute immediately whenever the atoms they depended on
-         This could cause performance issues in code with expensive
+         changed. This could cause performance issues in code with
-         reactions and frequent updates to state. However, this change
+         expensive reactions and frequent updates to state. However,
-         may break existing code that depends on the timing of
+         this change may break existing code that depends on the
-         side-effects from running reactions. "[:code "flush"]" can be
+         timing of side-effects from running
-         used to force outstanding reactions to run at a given
+         reactions. "[:code "flush"]" can be used to force outstanding
-         time."]
+         reactions to run at a given time."]
 
          [:li "Reactions now only trigger updates of dependent
          components and other reactions if they produce a new result,