support negative index

README.md

@@ -73,7 +73,7 @@ while (values.hasNext)
 }
 
 //set item at index 0
-s.setItem(0, 5);
+s.setItem(5, 0);
 s[0] = 5;
 s.first = 5;
 //last item also has index -1, item before last -2 and etc. (Ruby-like)
@@ -84,7 +84,7 @@ delete s[0];
 s.removeItem(0);
 ```
 *Stream is about 10x slower when accessed by index (`[index]`) and it seems to be Proxy overhead.
-If you need better performance (3x slower than Array) use methods to access Stream items: `getItem(index)` and `setItem(index, value)`.*
+If you need better performance (3x slower than Array) use methods to access Stream items: `getItem(index)` and `setItem(value, index)`.*
 
 ## Convert Stream to any collection
 ```as3

source/com/kemsky/Stream.as

@@ -445,7 +445,14 @@ package com.kemsky
          */
         public function getItem(index:int):*
         {
-            return source[index];
+            if(index >= 0)
+            {
+                return source[index];
+            }
+            else
+            {
+                return source[source.length + index];
+            }
         }
 
         /**
@@ -455,45 +462,65 @@ package com.kemsky
          * @example
          * <pre>
          *     var s:Stream = $(1, 2, 3);
-         *     s.setItem(1, 4);
+         *     s.setItem(4, 1);
          *     trace(s);
          *     //Stream{1, 4, 3}
          * </pre>
          * @internal mutable
          */
-        public function setItem(index:int, value:*):void
+        public function setItem(value:*, index:int):void
         {
-            source[index] = value;
+            if(index >= 0)
+            {
+                source[index] = value;
+            }
+            else
+            {
+                source[source.length + index] = value;
+            }
         }
 
         /**
          * Adds item to specified position.
          * @param index An integer that specifies the position in the list where the item is to be added to.
-         * @param value An item to add.
+         * @param value An item to add. Item will be added to the end of stream by default.
          * @example
          * <pre>
          *     var s:Stream = $(1, 2, 3);
-         *     s.addItem(1, 4);
+         *     s.addItem(4, 1);
          *     trace(s);
          *     //Stream{1, 4, 2, 3}
          * </pre>
          * @internal mutable
          */
-        public function addItem(index:int, value:*):void
+        public function addItem(value:*, index:int = 0):void
         {
-            if(index <= source.length)
+            if(arguments.length == 1)
+            {
+                index = source.length;
+            }
+
+            if(index < 0)
             {
+                index = source.length + index;
+            }
+
+            if(index < source.length)
+            {
+                //insert
                 source.splice(index, 0, value);
             }
             else
             {
+                //push
                 source[index] = value;
             }
         }
 
         /**
          * Removes item at specified position.
          * @param index An integer that specifies the position in the list.
+         * @return true if remove was successful.
          * @example
          * <pre>
          *     var s:Stream = $(1, 2, 3);
@@ -503,9 +530,16 @@ package com.kemsky
          * </pre>
          * @internal mutable
          */
-        public function removeItem(index:int):void
+        public function removeItem(index:int):Boolean
         {
-            delete this[index];
+            if(index < 0)
+            {
+                return (source.splice(source.length + index, 1) as Array).length > 0;
+            }
+            else
+            {
+                return (source.splice(index, 1) as Array).length > 0;
+            }
         }
 
         /**
@@ -2007,14 +2041,7 @@ package com.kemsky
             }
             else
             {
-                if(index < 0)
-                {
-                    source[index] = value;
-                }
-                else
-                {
-                    source[source.length + index] = value;
-                }
+                setItem(value, index);
             }
         }
 
@@ -2109,14 +2136,7 @@ package com.kemsky
                 return false;
             }
 
-            if(index < 0)
-            {
-                return (source.splice(source.length + index, 1) as Array).length > 0;
-            }
-            else
-            {
-                return (source.splice(index, 1) as Array).length > 0;
-            }
+            return removeItem(index);
         }
 
         /**

source/com/kemsky/support/ValueIterator.as

@@ -128,7 +128,7 @@ package com.kemsky.support
             {
                 throw new StreamError("Current item is not available");
             }
-            stream.setItem(_current, value);
+            stream.setItem(value, _current);
         }
 
         /**

testSrc/com/kemsky/TestStream.as

@@ -385,8 +385,8 @@ package com.kemsky
         public function testSet():void
         {
             var s:Stream = $(1, 2, 3);
-            s.setItem(2, 1);
-            s.setItem(0, 3);
+            s.setItem(1, 2);
+            s.setItem(3, 0);
             assertEquals(s[0], 3);
             assertEquals(s[1], 2);
             assertEquals(s[2], 1);
@@ -397,8 +397,8 @@ package com.kemsky
         public function testAdd():void
         {
             var s:Stream = $(1, 2, 3);
-            s.addItem(2, 1);
-            s.addItem(0, 3);
+            s.addItem(1, 2);
+            s.addItem(3, 0);
             //3, 1, 2, 1, 3
             assertEquals(s.length, 5);
             assertEquals(s[0], 3);
@@ -413,9 +413,13 @@ package com.kemsky
             assertEquals(d.last, 4);
 
             var e:Stream = $();
-            e.addItem(0, 4);
+            e.addItem(4, 0);
             assertEquals(e.length, 1);
-            assertEquals(e.last, 4);
+            assertEquals(e.first, 4);
+
+            e.addItem(4);
+            assertEquals(e.length, 2);
+            assertEquals(e.second, 4);
         }
 
         [Test]