1 files changed, 23 insertions, 0 deletions
diff --git a/lib/sortBy.js b/lib/sortBy.js
new file mode 100644
index 0000000..4f14823
--- /dev/null
+++ b/lib/sortBy.js
@@ -0,0 +1,23 @@
+'use strict';
+
+import arrayMap from 'lodash/_arrayMap';
+import property from 'lodash/_baseProperty';
+
+import map from './map';
+
+export default function sortBy (arr, iterator, cb) {
+    map(arr, function (x, cb) {
+        iterator(x, function (err, criteria) {
+            if (err) return cb(err);
+            cb(null, {value: x, criteria: criteria});
+        });
+    }, function (err, results) {
+        if (err) return cb(err);
+        cb(null, arrayMap(results.sort(comparator), property('value')));
+    });
+
+    function comparator(left, right) {
+        var a = left.criteria, b = right.criteria;
+        return a < b ? -1 : a > b ? 1 : 0;
+    }
+}