From c8a86b39d52158e2ffcbfe043c551b78c8e3d4ab Mon Sep 17 00:00:00 2001
From: Andrey Antukh <niwi@niwi.nz>
Date: Thu, 7 Jan 2016 19:01:50 +0200
Subject: [PATCH] Add syntax helper for define once unnamed global instances.

---
 frontend/uxbox/ui/workspace/base.cljs |  5 +++--
 frontend/uxbox/util/syntax.cljc       | 10 ++++++++++
 2 files changed, 13 insertions(+), 2 deletions(-)
 create mode 100644 frontend/uxbox/util/syntax.cljc

diff --git a/frontend/uxbox/ui/workspace/base.cljs b/frontend/uxbox/ui/workspace/base.cljs
index fc33de822..c3db3e696 100644
--- a/frontend/uxbox/ui/workspace/base.cljs
+++ b/frontend/uxbox/ui/workspace/base.cljs
@@ -1,4 +1,5 @@
 (ns uxbox.ui.workspace.base
+  (:require-macros [uxbox.util.syntax :refer [define-once]])
   (:require [beicon.core :as rx]
             [cats.labs.lens :as l]
             [uxbox.rstore :as rs]
@@ -88,7 +89,7 @@
        (rx/buffer 2 1)
        (rx/map coords-delta)))
 
-(defonce $$drag-subscription$$
+(define-once
   (as-> mouse-delta-s $
     (rx/filter #(deref shapes-dragging?) $)
     (rx/on-value $ (fn [delta]
@@ -113,7 +114,7 @@
      :width (- current-x start-x)
      :height (- current-y start-y)}))
 
-(defonce $$selrect-subscription$$
+(define-once
   (let [ss (as-> (rx/from-atom selrect-dragging?) $
              (rx/dedupe $)
              (rx/merge $ (rx/of false))
diff --git a/frontend/uxbox/util/syntax.cljc b/frontend/uxbox/util/syntax.cljc
new file mode 100644
index 000000000..f39c1439b
--- /dev/null
+++ b/frontend/uxbox/util/syntax.cljc
@@ -0,0 +1,10 @@
+(ns uxbox.util.syntax
+  (:refer-clojure :exclude [defonce]))
+
+(defmacro define-once
+  [& body]
+  (let [sym (gensym "uxbox-")]
+    `(cljs.core/defonce ~sym
+       (do ~@body
+           nil))))
+