Merge f133fbe256 into b72968dfb9

project.clj

@@ -7,7 +7,8 @@
                  [org.mongodb/mongo-java-driver "2.11.2"]
                  [com.novemberain/validateur    "1.5.0"]
                  [clojurewerkz/support          "0.19.0"]
-                 [ragtime/ragtime.core          "0.3.4"]]
+                 [ragtime/ragtime.core          "0.3.4"]
+                 [clj-yield                     "1.1"]]
   :test-selectors {:default     (fn [m]
                                   (and (not (:performance m))
                                        (not (:edge-features m))

src/clojure/monger/query.clj

@@ -18,7 +18,8 @@
             [monger.cursor :as cursor :refer [add-options]])
   (:import [com.mongodb DB DBCollection DBObject DBCursor ReadPreference]
            [java.util List])
-  (:use [monger conversion operators]))
+  (:use [monger conversion operators]
+        [yield]))
 
 
 ;;
@@ -65,6 +66,7 @@
 
 (defn exec
   [{ :keys [^DBCollection collection query fields skip limit sort batch-size hint snapshot read-preference keywordize-fields options] :or { limit 0 batch-size 256 skip 0 } }]
+  (with-yielding [y-out 1]
     (with-open [cursor (doto (.find collection (to-db-object query) (as-field-selector fields))
                        (.limit limit)
                        (.skip  skip)
@@ -77,9 +79,10 @@
         (.setReadPreference cursor read-preference))
       (when options
         (add-options cursor options))
-    (map (fn [x] (from-db-object x keywordize-fields))
-         cursor)))
-
+      (loop []
+        (when (.hasNext cursor)
+          (yield y-out (from-db-object (.next cursor) keywordize-fields))
+          (recur))))))
 ;;
 ;; API
 ;;