fail faster on js/Infinity && js/NaN since these cases much be tested…

… anyway - doing arithmetic on these cases is slow. Extra tests do incur a small perf hit when testing actual numbers.
ohpauleez · Sep 5, 2012 · ff4de29 · ff4de29
1 parent c7198c9
commit ff4de29
Showing 1 changed file with 3 additions and 2 deletions.
diff --git a/src/cljs/cljs/core.cljs b/src/cljs/cljs/core.cljs
@@ -1019,8 +1019,9 @@ reduces them without incurring seq initialization"
   "Returns true if n is an integer."
   [n]
   (and (number? n)
-       (coercive-= (js/parseFloat n) (js/parseInt n 10))
-       (not ^boolean (js/isNaN n))))
+       (not ^boolean (js/isNaN n))
+       (not (identical? n js/Infinity))
+       (== (js/parseFloat n) (js/parseInt n 10))))
 
 (defn ^boolean contains?
   "Returns true if key is present in the given collection, otherwise