From be063978495018b5b93c8374790ece5793c7a374 Mon Sep 17 00:00:00 2001
From: "Michael S. Klishin" <michael@novemberain.com>
Date: Mon, 28 Nov 2011 20:12:19 +0400
Subject: [PATCH] Introduce monger.collection/any?

Useful for detecting duplicate documents and so on
---
 src/monger/collection.clj       | 16 +++++++++++-----
 test/monger/test/collection.clj |  6 +++++-
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/src/monger/collection.clj b/src/monger/collection.clj
index f28d92a..95b1226 100644
--- a/src/monger/collection.clj
+++ b/src/monger/collection.clj
@@ -142,7 +142,7 @@
 ;;
 ;; monger.collection/count
 ;;
-(defn ^long count
+(defn count
   "Returns the number of documents in this collection.
 
   Takes optional conditions as an argument.
@@ -150,12 +150,18 @@
       (monger.collection/count collection)
 
       (monger.collection/count collection { :first_name \"Paul\" })"
+  (^long [^String collection]
+         (let [^DBCollection coll (.getCollection monger.core/*mongodb-database* collection)]
+           (.count coll)))
+  (^long [^String collection, ^Map conditions]
+         (let [^DBCollection coll (.getCollection monger.core/*mongodb-database* collection)]
+           (.count coll (to-db-object conditions)))))
+
+(defn any?
   ([^String collection]
-     (let [^DBCollection coll (.getCollection monger.core/*mongodb-database* collection)]
-       (.count coll)))
+     (> (count collection) 0))
   ([^String collection, ^Map conditions]
-     (let [^DBCollection coll (.getCollection monger.core/*mongodb-database* collection)]
-       (.count coll (to-db-object conditions)))))
+     (> (count collection conditions) 0)))
 
 
 ;; monger.collection/update
diff --git a/test/monger/test/collection.clj b/test/monger/test/collection.clj
index b1c5ed7..c1b3a34 100644
--- a/test/monger/test/collection.clj
+++ b/test/monger/test/collection.clj
@@ -79,9 +79,13 @@
                                     { :language "Clojure", :name "incanter" }
                                     { :language "Scala",   :name "akka" }] )
     (is (= 4 (mgcol/count collection)))
+    (is (mgcol/any? collection))
     (is (= 3 (mgcol/count collection { :language "Clojure" })))
+    (is (mgcol/any? collection { :language "Clojure" }))
     (is (= 1 (mgcol/count collection { :language "Scala"   })))
-    (is (= 0 (mgcol/count collection { :language "Python"  })))))
+    (is (mgcol/any? collection { :language "Scala" }))
+    (is (= 0 (mgcol/count collection { :language "Python"  })))
+    (is (not (mgcol/any? collection { :language "Python" })))))
 
 
 (deftest remove-all-documents-from-collection