From c500e7a4c67725a66c1c12da5ad847dfb42e2f30 Mon Sep 17 00:00:00 2001
From: coderaiser <mnemonic.enemy@gmail.com>
Date: Tue, 21 Jul 2015 04:32:24 -0400
Subject: [PATCH] feature(util) exec: each, eachSeries

---
 lib/util.js | 61 ++++++++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 49 insertions(+), 12 deletions(-)

diff --git a/lib/util.js b/lib/util.js
index 430e556b..c7698b4e 100644
--- a/lib/util.js
+++ b/lib/util.js
@@ -395,19 +395,56 @@
              * load functions thrue callbacks one-by-one
              * @param funcs {Array} - array of functions
              */
-            exec.series             = function(funcs) {
-                var func, callback,
-                    isArray     = Util.type.array(funcs);
-                
-                if (isArray) {
-                    func        = funcs.shift();
-                    
-                    callback    = function() {
-                        return exec.series(funcs);
+            exec.series             = function(funcs, callback) {
+                var fn,
+                    i           = funcs.length,
+                    check       = function(error) {
+                        var done;
+                        
+                        --i;
+                        
+                        if (!i || error) {
+                            done = true;
+                            exec(callback, error);
+                        }
+                        
+                        return done;
                     };
-                    
-                    exec(func, callback);
-                }
+                
+                if (!Array.isArray(funcs))
+                    throw(Error('funcs should be array!'));
+                
+                fn = funcs.shift();
+                
+                exec(fn, function(error) {
+                    if (!check(error))
+                        exec.series(funcs, callback);
+                });
+            };
+            
+            exec.each               = function(array, iterator, callback) {
+                var listeners = array.map(function(item) {
+                    return iterator.bind(null, item);
+                });
+                
+                if (!listeners.length)
+                    callback();
+                else
+                    exec.parallel(listeners, callback);
+            };
+                
+            exec.eachSeries         = function(array, iterator, callback) {
+                var listeners = array.map(function(item) {
+                    return iterator.bind(null, item);
+                });
+                
+                if (typeof callback !== 'function')
+                    throw Error('callback should be function');
+                
+                if (!listeners.length)
+                    callback();
+                else
+                    exec.series(listeners, callback);
             };
             
            /**