realized? for lazy seq in ClojureScript

experiment.patch

From 705930227b34365b95480941ee085f2e5a4e2a63 Mon Sep 17 00:00:00 2001
From: Mike Fikes <mike@fikesfarm.com>
Date: Fri, 1 Jan 2016 01:24:34 -0500
Subject: [PATCH] Experiment: realized? for lazy seq

---
 src/main/cljs/cljs/core.cljs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/main/cljs/cljs/core.cljs b/src/main/cljs/cljs/core.cljs
index c6ca522..f6db702 100644
--- a/src/main/cljs/cljs/core.cljs
+++ b/src/main/cljs/cljs/core.cljs
@@ -3014,6 +3014,10 @@ reduces them without incurring seq initialization"
         (set! fn nil)
         s)))
 
+  IPending
+  (-realized? [d]
+    (nil? fn))
+
   IWithMeta
   (-with-meta [coll meta] (LazySeq. meta fn s __hash))
 
-- 
2.5.4 (Apple Git-61)