From 65b611eb0fe7878704df190e36dedfd0a9071c3a Mon Sep 17 00:00:00 2001
From: Xuefeng Zhu <xzhu15@illinois.edu>
Date: Sat, 16 Apr 2016 00:29:04 -0500
Subject: [PATCH] refactor Header iterator methods

---
 fetch.js | 63 +++++++++++++++++++-------------------------------------
 1 file changed, 21 insertions(+), 42 deletions(-)

diff --git a/fetch.js b/fetch.js
index 5717106b..d0652dea 100644
--- a/fetch.js
+++ b/fetch.js
@@ -37,6 +37,24 @@
     return value
   }
 
+  // Build a destructive iterator for the value list
+  function iteratorFor(items) {
+    var iterator = {
+      next: function() {
+        var value = items.shift()
+        return {done: value === undefined, value: value}
+      }
+    }
+
+    if (support.iterable) {
+      iterator[Symbol.iterator] = function() {
+        return iterator
+      }
+    }
+
+    return iterator
+  }
+
   function Headers(headers) {
     this.map = {}
 
@@ -95,58 +113,19 @@
   Headers.prototype.keys = function() {
     var items = []
     this.forEach(function(value, name) { items.push(name) })
-    var iterator = {
-      next: function() {
-        var value = items.shift()
-        return {done: value === undefined, value: value}
-      }
-    }
-
-    if (support.iterable) {
-      iterator[Symbol.iterator] = function() {
-        return iterator
-      }
-    }
-
-    return iterator
+    return iteratorFor(items)
   }
 
   Headers.prototype.values = function() {
     var items = []
     this.forEach(function(value) { items.push(value) })
-    var iterator = {
-      next: function() {
-        var value = items.shift()
-        return {done: value === undefined, value: value}
-      }
-    }
-
-    if (support.iterable) {
-      iterator[Symbol.iterator] = function() {
-        return iterator
-      }
-    }
-
-    return iterator
+    return iteratorFor(items)
   }
 
   Headers.prototype.entries = function() {
     var items = []
     this.forEach(function(value, name) { items.push([name, value]) })
-    var iterator = {
-      next: function() {
-        var value = items.shift()
-        return {done: value === undefined, value: value}
-      }
-    }
-
-    if (support.iterable) {
-      iterator[Symbol.iterator] = function() {
-        return iterator
-      }
-    }
-
-    return iterator
+    return iteratorFor(items)
   }
 
   if (support.iterable) {