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+# diffpatcher
+
+[![Build Status](https://secure.travis-ci.org/Gozala/diffpatcher.png)](http://travis-ci.org/Gozala/diffpatcher)
+
+[![Browser support](https://ci.testling.com/Gozala/diffpatcher.png)](http://ci.testling.com/Gozala/diffpatcher)
+
+Diffpatcher is a small library that lets you treat hashes as if they were
+git repositories.
+
+## diff
+
+Diff function that takes two hashes and returns delta hash.
+
+```js
+var diff = require("diffpatcher/diff")
+
+diff({ a: { b: 1 }, c: { d: 2 } },      // hash#1
+     { a: { e: 3 }, c: { d: 4 } })      // hash#2
+
+// => {                                 // delta
+//      a: {
+//        b: null,        // -
+//        e: 3            // +
+//      },
+//      c: {
+//        d: 4            // ±
+//      }
+//    }
+```
+
+As you can see from the example above `delta` makes no real distinction between
+proprety upadate and property addition. Try to think of additions as an update
+from `undefined` to whatever it's being updated to.
+
+## patch
+
+Patch fuction takes a `hash` and a `delta` and returns a new `hash` which is
+just like orginial but with delta applied to it. Let's apply delta from the
+previous example to the first hash from the same example
+
+
+```js
+var patch = require("diffpatcher/patch")
+
+patch({ a: { b: 1 }, c: { d: 2 } },     // hash#1
+      {                                 // delta
+        a: {
+          b: null,        // -
+          e: 3            // +
+        },
+        c: {
+          d: 4            // ±
+        }
+      })
+
+// => { a: { e: 3 }, c: { d: 4 } }      // hash#2
+```
+
+That's about it really, just diffing hashes and applying thes diffs on them.
+
+
+### rebase
+
+And as Linus mentioned everything in git can be expressed with `rebase`, that
+also pretty much the case for `diffpatcher`. `rebase` takes `target` hash,
+and rebases `parent` onto it with `diff` applied.
+
+## Install
+
+    npm install diffpatcher