From 7277bbfd535e87e02f72e5dfc7c25cc7391c2928 Mon Sep 17 00:00:00 2001
From: Brandon Bloom <brandon@brandonbloom.name>
Date: Sun, 24 Jun 2012 17:45:30 -0700
Subject: [PATCH 1/3] defn hash-set

---
 src/cljs/cljs/core.cljs       |   15 ++++++++++-----
 test/cljs/cljs/core_test.cljs |    3 +++
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/src/cljs/cljs/core.cljs b/src/cljs/cljs/core.cljs
index d7ede71..2b13ed6 100644
--- a/src/cljs/cljs/core.cljs
+++ b/src/cljs/cljs/core.cljs
@@ -5696,14 +5696,19 @@ reduces them without incurring seq initialization"
 
 (set! cljs.core.PersistentTreeSet/EMPTY (PersistentTreeSet. nil (sorted-map) 0))
 
+(defn hash-set
+  ([] cljs.core.PersistentHashSet/EMPTY)
+  ([& keys]
+    (loop [in (seq keys)
+           out (transient cljs.core.PersistentHashSet/EMPTY)]
+      (if (seq in)
+        (recur (next in) (conj! out (first in)))
+        (persistent! out)))))
+
 (defn set
   "Returns a set of the distinct elements of coll."
   [coll]
-  (loop [in (seq coll)
-         out (transient cljs.core.PersistentHashSet/EMPTY)]
-    (if (seq in)
-      (recur (next in) (conj! out (first in)))
-      (persistent! out))))
+  (apply hash-set coll))
 
 (defn sorted-set
   "Returns a new sorted set with supplied keys."
diff --git a/test/cljs/cljs/core_test.cljs b/test/cljs/cljs/core_test.cljs
index 8f7668a..a80f8a7 100644
--- a/test/cljs/cljs/core_test.cljs
+++ b/test/cljs/cljs/core_test.cljs
@@ -488,8 +488,11 @@
 
   (assert (set []))
   (assert (= #{} (set [])))
+  (assert (= #{} (hash-set)))
+  (assert (identical? cljs.core.PersistentHashSet (type (hash-set))))
 
   (assert (= #{"foo"} (set ["foo"])))
+  (assert (= #{"foo"} (hash-set "foo")))
   (assert (= #{1 2 3} #{1 3 2}))
   (assert (= #{#{1 2 3} [4 5 6] {7 8} 9 10}
              #{10 9 [4 5 6] {7 8} #{1 2 3}}))
-- 
1.7.9.1


From 9ca568139dceeac5f0ec9c8d91e499855da70878 Mon Sep 17 00:00:00 2001
From: Brandon Bloom <brandon@brandonbloom.name>
Date: Sun, 24 Jun 2012 17:51:06 -0700
Subject: [PATCH 2/3] Add set construction benchmarks

---
 benchmark/cljs/benchmark_runner.cljs |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/benchmark/cljs/benchmark_runner.cljs b/benchmark/cljs/benchmark_runner.cljs
index 410b262..c7a4668 100644
--- a/benchmark/cljs/benchmark_runner.cljs
+++ b/benchmark/cljs/benchmark_runner.cljs
@@ -109,6 +109,12 @@
 (simple-benchmark [coll cljs.core.PersistentHashMap/EMPTY] (assoc coll :f0 1) 1000000)
 (println)
 
+(println ";;; set ops")
+(simple-benchmark [] #{} 100000)
+(simple-benchmark [] #{1 2 3} 100000)
+(simple-benchmark [coll #{1 2 3}] (conj coll 4) 100000)
+(println)
+
 (println ";;; seq ops")
 (simple-benchmark [coll (range 500000)] (reduce + coll) 1)
 (println)
@@ -135,4 +141,4 @@
 (simple-benchmark [r r] (last r) 1)
 (println)
 
-(println "\n")
\ No newline at end of file
+(println "\n")
-- 
1.7.9.1


From 4e35410ee99f58b9637d1e87d04f175fd9dc7102 Mon Sep 17 00:00:00 2001
From: Brandon Bloom <brandon@brandonbloom.name>
Date: Sun, 24 Jun 2012 17:56:26 -0700
Subject: [PATCH 3/3] Faster set construction

---
 src/clj/cljs/compiler.clj |    6 ++++--
 src/cljs/cljs/core.cljs   |    9 +++++++++
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/clj/cljs/compiler.clj b/src/clj/cljs/compiler.clj
index dac3ca3..b33a8d2 100644
--- a/src/clj/cljs/compiler.clj
+++ b/src/clj/cljs/compiler.clj
@@ -249,8 +249,10 @@
 (defmethod emit :set
   [{:keys [items env]}]
   (emit-wrap env
-    (emits "cljs.core.set(["
-           (comma-sep items) "])")))
+    (if (empty? items)
+      (emits "cljs.core.PersistentHashSet.EMPTY")
+      (emits "cljs.core.PersistentHashSet.fromArray(["
+             (comma-sep items) "])"))))
 
 (defmethod emit :constant
   [{:keys [form env]}]
diff --git a/src/cljs/cljs/core.cljs b/src/cljs/cljs/core.cljs
index 2b13ed6..46e4684 100644
--- a/src/cljs/cljs/core.cljs
+++ b/src/cljs/cljs/core.cljs
@@ -5589,6 +5589,15 @@ reduces them without incurring seq initialization"
 
 (set! cljs.core.PersistentHashSet/EMPTY (PersistentHashSet. nil (hash-map) 0))
 
+(set! cljs.core.PersistentHashSet/fromArray
+      (fn [items]
+        (let [len (count items)]
+          (loop [i   0
+                 out (transient cljs.core.PersistentHashSet/EMPTY)]
+            (if (< i len)
+              (recur (inc i) (conj! out (aget items i)))
+              (persistent! out))))))
+
 (deftype TransientHashSet [^:mutable transient-map]
   ITransientCollection
   (-conj! [tcoll o]
-- 
1.7.9.1