v13.0.0-22 -- distribution files

13.0.0-22
add indexeddb example
2017-10-07 00:46:32 +02:00 · 2017-10-07 00:42:06 +02:00 · 2017-10-07 00:40:34 +02:00 · 2017-10-07 00:39:26 +02:00 · 2017-10-02 15:52:11 +02:00 · 2017-10-02 15:50:56 +02:00
40 changed files with 33815 additions and 2251 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 node_modules
 bower_components
 /y.*
+/examples/yjs-dist.js*
--- a/examples/html-editor/index.html
+++ b/examples/html-editor/index.html
@@ -0,0 +1,11 @@
+<!DOCTYPE html>
+<html>
+</head>
+  <!-- jquery is not required for y-xml. It is just here for convenience, and to test batch operations. -->
+  <script src="https://code.jquery.com/jquery-3.2.1.min.js"></script>
+  <script src="../yjs-dist.js"></script>
+  <script src="./index.js"></script>
+</head>
+<body contenteditable="true">
+</body>
+</html>
--- a/examples/html-editor/index.js
+++ b/examples/html-editor/index.js
@@ -0,0 +1,21 @@
+/* global Y */
+
+// initialize a shared object. This function call returns a promise!
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    url: 'http://127.0.0.1:1234',
+    room: 'html-editor-example6'
+    // maxBufferLength: 100
+  },
+  share: {
+    xml: 'XmlFragment()' // y.share.xml is of type Y.Xml with tagname "p"
+  }
+}).then(function (y) {
+  window.yXml = y
+  // Bind children of XmlFragment to the document.body
+  window.yXml.share.xml.bindToDom(document.body)
+})
--- a/examples/indexeddb/index.html
+++ b/examples/indexeddb/index.html
@@ -0,0 +1,21 @@
+<!DOCTYPE html>
+<html>
+  <head>
+  </head>
+  <body>
+    <div id="codeMirrorContainer"></div>
+    <script src="../bower_components/codemirror/lib/codemirror.js"></script>
+    <script src="../bower_components/codemirror/mode/javascript/javascript.js"></script>
+    <link rel="stylesheet" href="../bower_components/codemirror/lib/codemirror.css">
+    <style>
+      .CodeMirror {
+        position: fixed;
+        top: 0;
+        left: 0;
+        height: 100%;
+        width: 100%;
+      }
+    </style>
+    <script type="module" src="./index.js"></script>
+  </body>
+</html>
--- a/examples/indexeddb/index.js
+++ b/examples/indexeddb/index.js
@@ -0,0 +1,24 @@
+/* global Y, CodeMirror */
+
+// initialize a shared object. This function call returns a promise!
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'codemirror-example'
+  },
+  sourceDir: '/bower_components',
+  share: {
+    codemirror: 'Text' // y.share.codemirror is of type Y.Text
+  }
+}).then(function (y) {
+  window.yCodeMirror = y
+
+  var editor = CodeMirror(document.querySelector('#codeMirrorContainer'), {
+    mode: 'javascript',
+    lineNumbers: true
+  })
+  y.share.codemirror.bindCodeMirror(editor)
+})
--- a/examples/infiniteyjs/index.html
+++ b/examples/infiniteyjs/index.html
@@ -0,0 +1,58 @@
+<!DOCTYPE html>
+<html>
+<body>
+  <style>
+    .wrapper {
+      display: grid;
+      grid-template-columns: repeat(3, 1fr);
+      grid-gap: 7px;
+    }
+    .one {
+      grid-column: 1 ;
+    }
+    .two { 
+      grid-column: 2;
+    }
+    .three {
+      grid-column: 3;
+    }
+    textarea {
+      width: calc(100% - 10px)
+    }
+    .editor-container {
+      background-color: #4caf50;
+      padding: 4px 5px 10px 5px;
+      border-radius: 11px;
+    }
+    .editor-container[disconnected] {
+      background-color: red;
+    }
+    .disconnected-info {
+      display: none;
+    }
+    .editor-container[disconnected] .disconnected-info {
+      display: inline;
+    }
+  </style>
+  <div class="wrapper">
+    <div id="container1" class="one editor-container">
+      <h1>Server 1 <span class="disconnected-info">(disconnected)</span></h1>
+      <textarea id="textarea1" rows=40 autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"></textarea>
+    </div>
+    <div id="container2" class="two editor-container">
+      <h1>Server 2 <span class="disconnected-info">(disconnected)</span></h1>
+      <textarea id="textarea2" rows=40 autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"></textarea>
+    </div>
+    <div id="container3" class="three editor-container">
+      <h1>Server 3 <span class="disconnected-info">(disconnected)</span></h1>
+      <textarea id="textarea3" rows=40 autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"></textarea>
+    </div>
+  </div>
+  <script src="../../y.js"></script>
+  <script src="../../../y-array/y-array.js"></script>
+  <script src="../../../y-text/dist/y-text.js"></script>
+  <script src="../../../y-memory/y-memory.js"></script>
+  <script src="../../../y-websockets-client/y-websockets-client.js"></script>
+  <script src="./index.js"></script>
+</body>
+</html>
--- a/examples/infiniteyjs/index.js
+++ b/examples/infiniteyjs/index.js
@@ -0,0 +1,64 @@
+/* global Y */
+
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'Textarea-example',
+    url: 'https://yjs-v13.herokuapp.com/'
+  },
+  share: {
+    textarea: 'Text'
+  }
+}).then(function (y) {
+  window.y1 = y
+  y.share.textarea.bind(document.getElementById('textarea1'))
+})
+
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'Textarea-example',
+    url: 'https://yjs-v13-second.herokuapp.com/'
+  },
+  share: {
+    textarea: 'Text'
+  }
+}).then(function (y) {
+  window.y2 = y
+  y.share.textarea.bind(document.getElementById('textarea2'))
+  y.connector.socket.on('connection', function () {
+    document.getElementById('container2').removeAttribute('disconnected')
+  })
+  y.connector.socket.on('disconnect', function () {
+    document.getElementById('container2').setAttribute('disconnected', true)
+  })
+})
+
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'Textarea-example',
+    url: 'https://yjs-v13-third.herokuapp.com/'
+  },
+  share: {
+    textarea: 'Text'
+  }
+}).then(function (y) {
+  window.y3 = y
+  y.share.textarea.bind(document.getElementById('textarea3'))
+  y.connector.socket.on('connection', function () {
+    document.getElementById('container3').removeAttribute('disconnected')
+  })
+  y.connector.socket.on('disconnect', function () {
+    document.getElementById('container3').setAttribute('disconnected', true)
+  })
+})
--- a/examples/package.json
+++ b/examples/package.json
@@ -2,6 +2,10 @@
  "name": "examples",
  "version": "0.0.0",
  "description": "",
+  "scripts": {
+    "dist": "rollup -c",
+    "watch": "rollup -cw"
+  },
  "author": "Kevin Jahns",
  "license": "MIT",
  "dependencies": {
--- a/examples/rollup.config.js
+++ b/examples/rollup.config.js
@@ -0,0 +1,27 @@
+import nodeResolve from 'rollup-plugin-node-resolve'
+import commonjs from 'rollup-plugin-commonjs'
+
+var pkg = require('./package.json')
+
+export default {
+  entry: 'yjs-dist.esm',
+  dest: 'yjs-dist.js',
+  moduleName: 'Y',
+  format: 'umd',
+  plugins: [
+    nodeResolve({
+      main: true,
+      module: true,
+      browser: true
+    }),
+    commonjs()
+  ],
+  sourceMap: true,
+  banner: `
+/**
+ * ${pkg.name} - ${pkg.description}
+ * @version v${pkg.version}
+ * @license ${pkg.license}
+ */
+`
+}
--- a/examples/textarea/index.html
+++ b/examples/textarea/index.html
@@ -4,8 +4,7 @@
  <textarea style="width:80%;" rows=40 id="textfield" autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"></textarea>
  <script src="../../y.js"></script>
  <script src="../../../y-array/y-array.js"></script>
-  <script src="../../../y-text/dist/y-text.js"></script>
-  <script src="../../../y-memory/y-memory.js"></script>
+  <script src="../../../y-text/y-text.js"></script>
  <script src="../../../y-websockets-client/y-websockets-client.js"></script>
  <script src="./index.js"></script>
 </body>
--- a/examples/textarea/index.js
+++ b/examples/textarea/index.js
@@ -1,9 +1,5 @@
 /* global Y */

-// eslint-disable-next-line
-let search = new URLSearchParams(location.search)
-let url = search.get('url')
-
 // initialize a shared object. This function call returns a promise!
 Y({
  db: {
@@ -11,18 +7,17 @@ Y({
  },
  connector: {
    name: 'websockets-client',
-    room: 'Textarea-example',
-    url: url || 'http://127.0.0.1:1234'
+    room: 'Textarea-example2',
+    // url: '//localhost:1234',
+    url: 'https://yjs-v13.herokuapp.com/'
  },
-  sourceDir: '/bower_components',
  share: {
-    textarea: 'Text', // y.share.textarea is of type Y.Text
-    test: 'Array'
-  }
+    textarea: 'Text'
+  },
+  timeout: 5000 // reject if no connection was established within 5 seconds
 }).then(function (y) {
  window.yTextarea = y

  // bind the textarea to a shared text element
  y.share.textarea.bind(document.getElementById('textfield'))
-  // thats it..
 })
--- a/examples/xml/index.html
+++ b/examples/xml/index.html
@@ -1,8 +1,9 @@
 <!DOCTYPE html>
 <html>
 </head>
-  <script src="../bower_components/yjs/y.js"></script>
-  <script src="../bower_components/jquery/dist/jquery.min.js"></script>
+  <!-- jquery is not required for y-xml. It is just here for convenience, and to test batch operations. -->
+  <script src="https://code.jquery.com/jquery-3.2.1.min.js"></script>
+  <script src="../yjs-dist.js"></script>
  <script src="./index.js"></script>
 </head>
 <body>
--- a/examples/xml/index.js
+++ b/examples/xml/index.js
@@ -7,6 +7,8 @@ Y({
  },
  connector: {
    name: 'websockets-client',
+    // url: 'http://127.0.0.1:1234',
+    url: 'http://192.168.178.81:1234',
    room: 'Xml-example'
  },
  sourceDir: '/bower_components',
--- a/examples/yjs-dist.esm
+++ b/examples/yjs-dist.esm
@@ -0,0 +1,12 @@
+
+import Y from '../src/y.js'
+import yArray from '../../y-array/src/y-array.js'
+import yIndexedDB from '../../y-indexeddb/src/y-indexeddb.js'
+import yMap from '../../y-map/src/y-map.js'
+import yText from '../../y-text/src/y-text.js'
+import yXml from '../../y-xml/src/y-xml.js'
+import yWebsocketsClient from '../../y-websockets-client/src/y-websockets-client.js'
+
+Y.extend(yArray, yIndexedDB, yMap, yText, yXml, yWebsocketsClient)
+
+export default Y
--- a/package-lock.json
+++ b/package-lock.json
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
  "name": "yjs",
-  "version": "13.0.0-13",
+  "version": "13.0.0-22",
  "description": "A framework for real-time p2p shared editing on any data",
  "main": "./y.node.js",
  "browser": "./y.js",
@@ -10,6 +10,7 @@
    "debug": "concurrently 'rollup -wc rollup.test.js' 'cutest-serve y.test.js -o'",
    "lint": "standard",
    "dist": "rollup -c rollup.browser.js; rollup -c rollup.node.js",
+    "watch": "concurrently 'rollup -wc rollup.browser.js' 'rollup -wc rollup.node.js'",
    "postversion": "npm run dist",
    "postpublish": "tag-dist-files --overwrite-existing-tag"
  },
--- a/rollup.browser.js
+++ b/rollup.browser.js
@@ -1,4 +1,3 @@
-import inject from 'rollup-plugin-inject'
 import babel from 'rollup-plugin-babel'
 import uglify from 'rollup-plugin-uglify'
 import nodeResolve from 'rollup-plugin-node-resolve'
@@ -16,12 +15,7 @@ export default {
      browser: true
    }),
    commonjs(),
-    babel({
-      runtimeHelpers: true
-    }),
-    inject({
-      regeneratorRuntime: 'regenerator-runtime'
-    }),
+    babel(),
    uglify({
      output: {
        comments: function (node, comment) {
--- a/rollup.test.js
+++ b/rollup.test.js
@@ -3,7 +3,7 @@ import commonjs from 'rollup-plugin-commonjs'
 import multiEntry from 'rollup-plugin-multi-entry'

 export default {
-  entry: 'test/*',
+  entry: 'test/*.js',
  moduleName: 'y-tests',
  format: 'umd',
  plugins: [
--- a/src/Connector.js
+++ b/src/Connector.js
@@ -42,6 +42,11 @@ export default function extendConnector (Y/* :any */) {
      if (opts.generateUserId !== false) {
        this.setUserId(Y.utils.generateUserId())
      }
+      if (opts.maxBufferLength == null) {
+        this.maxBufferLength = -1
+      } else {
+        this.maxBufferLength = opts.maxBufferLength
+      }
    }

    reconnect () {
@@ -105,6 +110,7 @@ export default function extendConnector (Y/* :any */) {
        }
      }
    }
+
    userJoined (user, role, auth) {
      if (role == null) {
        throw new Error('You must specify the role of the joined user!')
@@ -133,6 +139,7 @@ export default function extendConnector (Y/* :any */) {
      }
      this._syncWithUser(user)
    }
+
    // Execute a function _when_ we are connected.
    // If not connected, wait until connected
    whenSynced (f) {
@@ -142,18 +149,20 @@ export default function extendConnector (Y/* :any */) {
        this.whenSyncedListeners.push(f)
      }
    }
+
    _syncWithUser (userid) {
      if (this.role === 'slave') {
        return // "The current sync has not finished or this is controlled by a master!"
      }
      sendSyncStep1(this, userid)
    }
+
    _fireIsSyncedListeners () {
      this.y.db.whenTransactionsFinished().then(() => {
        if (!this.isSynced) {
          this.isSynced = true
          // It is safer to remove this!
-          // TODO: remove: yield * this.garbageCollectAfterSync()
+          // TODO: remove: this.garbageCollectAfterSync()
          // call whensynced listeners
          for (var f of this.whenSyncedListeners) {
            f()
@@ -162,6 +171,7 @@ export default function extendConnector (Y/* :any */) {
        }
      })
    }
+
    send (uid, buffer) {
      if (!(buffer instanceof ArrayBuffer || buffer instanceof Uint8Array)) {
        throw new Error('Expected Message to be an ArrayBuffer or Uint8Array - please don\'t use this method to send custom messages')
@@ -169,6 +179,7 @@ export default function extendConnector (Y/* :any */) {
      this.log('%s: Send \'%y\' to %s', this.userId, buffer, uid)
      this.logMessage('Message: %Y', buffer)
    }
+
    broadcast (buffer) {
      if (!(buffer instanceof ArrayBuffer || buffer instanceof Uint8Array)) {
        throw new Error('Expected Message to be an ArrayBuffer or Uint8Array - please don\'t use this method to send custom messages')
@@ -176,6 +187,7 @@ export default function extendConnector (Y/* :any */) {
      this.log('%s: Broadcast \'%y\'', this.userId, buffer)
      this.logMessage('Message: %Y', buffer)
    }
+
    /*
      Buffer operations, and broadcast them when ready.
    */
@@ -190,14 +202,19 @@ export default function extendConnector (Y/* :any */) {
          encoder.writeVarString(self.opts.room)
          encoder.writeVarString('update')
          let ops = self.broadcastOpBuffer
-          self.broadcastOpBuffer = []
          let length = ops.length
-          encoder.writeUint32(length)
-          for (var i = 0; i < length; i++) {
+          let encoderPosLen = encoder.pos
+          encoder.writeUint32(0)
+          for (var i = 0; i < length && (self.maxBufferLength < 0 || encoder.length < self.maxBufferLength); i++) {
            let op = ops[i]
            Y.Struct[op.struct].binaryEncode(encoder, op)
          }
+          encoder.setUint32(encoderPosLen, i)
+          self.broadcastOpBuffer = ops.slice(i)
          self.broadcast(encoder.createBuffer())
+          if (i !== length) {
+            self.whenRemoteResponsive().then(broadcastOperations)
+          }
        }
      }
      if (this.broadcastOpBuffer.length === 0) {
@@ -207,6 +224,21 @@ export default function extendConnector (Y/* :any */) {
        this.broadcastOpBuffer = this.broadcastOpBuffer.concat(ops)
      }
    }
+
+    /*
+     * Somehow check the responsiveness of the remote clients/server
+     * Default behavior:
+     *   Wait 100ms before broadcasting the next batch of operations
+     *
+     * Only used when maxBufferLength is set
+     *
+     */
+    whenRemoteResponsive () {
+      return new Promise(function (resolve) {
+        setTimeout(resolve, 100)
+      })
+    }
+
    /*
      You received a raw message, and you know that it is intended for Yjs. Then call this function.
    */
@@ -224,14 +256,11 @@ export default function extendConnector (Y/* :any */) {
      encoder.writeVarString(roomname)
      let messageType = decoder.readVarString()
      let senderConn = this.connections.get(sender)
-
      this.log('%s: Receive \'%s\' from %s', this.userId, messageType, sender)
      this.logMessage('Message: %Y', buffer)
-
      if (senderConn == null && !skipAuth) {
        throw new Error('Received message from unknown peer!')
      }
-
      if (messageType === 'sync step 1' || messageType === 'sync step 2') {
        let auth = decoder.readVarUint()
        if (senderConn.auth == null) {
@@ -284,97 +313,6 @@ export default function extendConnector (Y/* :any */) {
        this._fireIsSyncedListeners()
      }
    }
-
-    /*
-      Currently, the HB encodes operations as JSON. For the moment I want to keep it
-      that way. Maybe we support encoding in the HB as XML in the future, but for now I don't want
-      too much overhead. Y is very likely to get changed a lot in the future
-
-      Because we don't want to encode JSON as string (with character escaping, wich makes it pretty much unreadable)
-      we encode the JSON as XML.
-
-      When the HB support encoding as XML, the format should look pretty much like this.
-
-      does not support primitive values as array elements
-      expects an ltx (less than xml) object
-    */
-    parseMessageFromXml (m/* :any */) {
-      function parseArray (node) {
-        for (var n of node.children) {
-          if (n.getAttribute('isArray') === 'true') {
-            return parseArray(n)
-          } else {
-            return parseObject(n)
-          }
-        }
-      }
-      function parseObject (node/* :any */) {
-        var json = {}
-        for (var attrName in node.attrs) {
-          var value = node.attrs[attrName]
-          var int = parseInt(value, 10)
-          if (isNaN(int) || ('' + int) !== value) {
-            json[attrName] = value
-          } else {
-            json[attrName] = int
-          }
-        }
-        for (var n/* :any */ in node.children) {
-          var name = n.name
-          if (n.getAttribute('isArray') === 'true') {
-            json[name] = parseArray(n)
-          } else {
-            json[name] = parseObject(n)
-          }
-        }
-        return json
-      }
-      parseObject(m)
-    }
-    /*
-      encode message in xml
-      we use string because Strophe only accepts an "xml-string"..
-      So {a:4,b:{c:5}} will look like
-      <y a="4">
-        <b c="5"></b>
-      </y>
-      m - ltx element
-      json - Object
-    */
-    encodeMessageToXml (msg, obj) {
-      // attributes is optional
-      function encodeObject (m, json) {
-        for (var name in json) {
-          var value = json[name]
-          if (name == null) {
-            // nop
-          } else if (value.constructor === Object) {
-            encodeObject(m.c(name), value)
-          } else if (value.constructor === Array) {
-            encodeArray(m.c(name), value)
-          } else {
-            m.setAttribute(name, value)
-          }
-        }
-      }
-      function encodeArray (m, array) {
-        m.setAttribute('isArray', 'true')
-        for (var e of array) {
-          if (e.constructor === Object) {
-            encodeObject(m.c('array-element'), e)
-          } else {
-            encodeArray(m.c('array-element'), e)
-          }
-        }
-      }
-      if (obj.constructor === Object) {
-        encodeObject(msg.c('y', { xmlns: 'http://y.ninja/connector-stanza' }), obj)
-      } else if (obj.constructor === Array) {
-        encodeArray(msg.c('y', { xmlns: 'http://y.ninja/connector-stanza' }), obj)
-      } else {
-        throw new Error("I can't encode this json!")
-      }
-    }
  }
  Y.AbstractConnector = AbstractConnector
 }
--- a/src/Database.js
+++ b/src/Database.js
@@ -85,11 +85,11 @@ export default function extendDatabase (Y /* :any */) {
              console.warn('gc should be empty when not synced!')
            }
            return new Promise((resolve) => {
-              os.requestTransaction(function * () {
+              os.requestTransaction(function () {
                if (os.y.connector != null && os.y.connector.isSynced) {
                  for (var i = 0; i < os.gc2.length; i++) {
                    var oid = os.gc2[i]
-                    yield * this.garbageCollectOperation(oid)
+                    this.garbageCollectOperation(oid)
                  }
                  os.gc2 = os.gc1
                  os.gc1 = []
@@ -197,15 +197,15 @@ export default function extendDatabase (Y /* :any */) {
      this.gc = false
      this.gcTimeout = -1
      return new Promise(function (resolve) {
-        self.requestTransaction(function * () {
+        self.requestTransaction(function () {
          var ungc /* :Array<Struct> */ = self.gc1.concat(self.gc2)
          self.gc1 = []
          self.gc2 = []
          for (var i = 0; i < ungc.length; i++) {
-            var op = yield * this.getOperation(ungc[i])
+            var op = this.getOperation(ungc[i])
            if (op != null) {
              delete op.gc
-              yield * this.setOperation(op)
+              this.setOperation(op)
            }
          }
          resolve()
@@ -224,7 +224,7 @@ export default function extendDatabase (Y /* :any */) {

      returns true iff op was added to GC
    */
-    * addToGarbageCollector (op, left) {
+    addToGarbageCollector (op, left) {
      if (
        op.gc == null &&
        op.deleted === true &&
@@ -235,12 +235,12 @@ export default function extendDatabase (Y /* :any */) {
        if (left != null && left.deleted === true) {
          gc = true
        } else if (op.content != null && op.content.length > 1) {
-          op = yield * this.getInsertionCleanStart([op.id[0], op.id[1] + 1])
+          op = this.getInsertionCleanStart([op.id[0], op.id[1] + 1])
          gc = true
        }
        if (gc) {
          op.gc = true
-          yield * this.setOperation(op)
+          this.setOperation(op)
          this.store.queueGarbageCollector(op.id)
          return true
        }
@@ -265,7 +265,7 @@ export default function extendDatabase (Y /* :any */) {
        }
      }
    }
-    * destroy () {
+    destroy () {
      clearTimeout(this.gcInterval)
      this.gcInterval = null
      this.stopRepairCheck()
@@ -274,9 +274,9 @@ export default function extendDatabase (Y /* :any */) {
      if (!this.userIdPromise.inProgress) {
        this.userIdPromise.inProgress = true
        var self = this
-        self.requestTransaction(function * () {
+        self.requestTransaction(function () {
          self.userId = userId
-          var state = yield * this.getState(userId)
+          var state = this.getState(userId)
          self.opClock = state.clock
          self.userIdPromise.resolve(userId)
        })
@@ -355,7 +355,7 @@ export default function extendDatabase (Y /* :any */) {
      this.listenersByIdRequestPending = true
      var store = this

-      this.requestTransaction(function * () {
+      this.requestTransaction(function () {
        var exeNow = store.listenersByIdExecuteNow
        store.listenersByIdExecuteNow = []

@@ -366,7 +366,7 @@ export default function extendDatabase (Y /* :any */) {

        for (let key = 0; key < exeNow.length; key++) {
          let o = exeNow[key].op
-          yield * store.tryExecute.call(this, o)
+          store.tryExecute.call(this, o)
        }

        for (var sid in ls) {
@@ -374,9 +374,9 @@ export default function extendDatabase (Y /* :any */) {
          var id = JSON.parse(sid)
          var op
          if (typeof id[1] === 'string') {
-            op = yield * this.getOperation(id)
+            op = this.getOperation(id)
          } else {
-            op = yield * this.getInsertion(id)
+            op = this.getInsertion(id)
          }
          if (op == null) {
            store.listenersById[sid] = l
@@ -385,7 +385,7 @@ export default function extendDatabase (Y /* :any */) {
              let listener = l[i]
              let o = listener.op
              if (--listener.missing === 0) {
-                yield * store.tryExecute.call(this, o)
+                store.tryExecute.call(this, o)
              }
            }
          }
@@ -402,15 +402,15 @@ export default function extendDatabase (Y /* :any */) {
    addOperation: any;
    whenOperationsExist: any;
    */
-    * tryExecute (op) {
-      this.store.addToDebug('yield * this.store.tryExecute.call(this, ', JSON.stringify(op), ')')
+    tryExecute (op) {
+      this.store.addToDebug('this.store.tryExecute.call(this, ', JSON.stringify(op), ')')
      if (op.struct === 'Delete') {
-        yield * Y.Struct.Delete.execute.call(this, op)
+        Y.Struct.Delete.execute.call(this, op)
        // this is now called in Transaction.deleteOperation!
-        // yield * this.store.operationAdded(this, op)
+        // this.store.operationAdded(this, op)
      } else {
        // check if this op was defined
-        var defined = yield * this.getInsertion(op.id)
+        var defined = this.getInsertion(op.id)
        while (defined != null && defined.content != null) {
          // check if this op has a longer content in the case it is defined
          if (defined.id[1] + defined.content.length < op.id[1] + op.content.length) {
@@ -419,23 +419,23 @@ export default function extendDatabase (Y /* :any */) {
            op.id = [op.id[0], op.id[1] + overlapSize]
            op.left = Y.utils.getLastId(defined)
            op.origin = op.left
-            defined = yield * this.getOperation(op.id) // getOperation suffices here
+            defined = this.getOperation(op.id) // getOperation suffices here
          } else {
            break
          }
        }
        if (defined == null) {
          var opid = op.id
-          var isGarbageCollected = yield * this.isGarbageCollected(opid)
+          var isGarbageCollected = this.isGarbageCollected(opid)
          if (!isGarbageCollected) {
            // TODO: reduce number of get / put calls for op ..
-            yield * Y.Struct[op.struct].execute.call(this, op)
-            yield * this.addOperation(op)
-            yield * this.store.operationAdded(this, op)
+            Y.Struct[op.struct].execute.call(this, op)
+            this.addOperation(op)
+            this.store.operationAdded(this, op)
            // operationAdded can change op..
-            op = yield * this.getOperation(opid)
+            op = this.getOperation(opid)
            // if insertion, try to combine with left
-            yield * this.tryCombineWithLeft(op)
+            this.tryCombineWithLeft(op)
          }
        }
      }
@@ -452,15 +452,15 @@ export default function extendDatabase (Y /* :any */) {
     * Always:
     *   * Call type
     */
-    * operationAdded (transaction, op) {
+    operationAdded (transaction, op) {
      if (op.struct === 'Delete') {
        var type = this.initializedTypes[JSON.stringify(op.targetParent)]
        if (type != null) {
-          yield * type._changed(transaction, op)
+          type._changed(transaction, op)
        }
      } else {
        // increase SS
-        yield * transaction.updateState(op.id[0])
+        transaction.updateState(op.id[0])
        var opLen = op.content != null ? op.content.length : 1
        for (let i = 0; i < opLen; i++) {
          // notify whenOperation listeners (by id)
@@ -480,9 +480,9 @@ export default function extendDatabase (Y /* :any */) {

        // if parent is deleted, mark as gc'd and return
        if (op.parent != null) {
-          var parentIsDeleted = yield * transaction.isDeleted(op.parent)
+          var parentIsDeleted = transaction.isDeleted(op.parent)
          if (parentIsDeleted) {
-            yield * transaction.deleteList(op.id)
+            transaction.deleteList(op.id)
            return
          }
        }
@@ -490,7 +490,7 @@ export default function extendDatabase (Y /* :any */) {
        // notify parent, if it was instanciated as a custom type
        if (t != null) {
          let o = Y.utils.copyOperation(op)
-          yield * t._changed(transaction, o)
+          t._changed(transaction, o)
        }
        if (!op.deleted) {
          // Delete if DS says this is actually deleted
@@ -499,18 +499,19 @@ export default function extendDatabase (Y /* :any */) {
            // TODO: !! console.log('TODO: change this before commiting')
          for (let i = 0; i < len; i++) {
            var id = [startId[0], startId[1] + i]
-            var opIsDeleted = yield * transaction.isDeleted(id)
+            var opIsDeleted = transaction.isDeleted(id)
            if (opIsDeleted) {
              var delop = {
                struct: 'Delete',
                target: id
              }
-              yield * this.tryExecute.call(transaction, delop)
+              this.tryExecute.call(transaction, delop)
            }
          }
        }
      }
    }
+
    whenTransactionsFinished () {
      if (this.transactionInProgress) {
        if (this.transactionsFinished == null) {
@@ -528,6 +529,7 @@ export default function extendDatabase (Y /* :any */) {
        return Promise.resolve()
      }
    }
+
    // Check if there is another transaction request.
    // * the last transaction is always a flush :)
    getNextRequest () {
@@ -542,8 +544,8 @@ export default function extendDatabase (Y /* :any */) {
          return null
        } else {
          this.transactionIsFlushed = true
-          return function * () {
-            yield * this.flush()
+          return function () {
+            this.flush()
          }
        }
      } else {
@@ -570,13 +572,13 @@ export default function extendDatabase (Y /* :any */) {
      Init type. This is called when a remote operation is retrieved, and transformed to a type
      TODO: delete type from store.initializedTypes[id] when corresponding id was deleted!
    */
-    * initType (id, args) {
+    initType (id, args) {
      var sid = JSON.stringify(id)
      var t = this.store.initializedTypes[sid]
      if (t == null) {
-        var op/* :MapStruct | ListStruct */ = yield * this.getOperation(id)
+        var op/* :MapStruct | ListStruct */ = this.getOperation(id)
        if (op != null) {
-          t = yield * Y[op.type].typeDefinition.initType.call(this, this.store, op, args)
+          t = Y[op.type].typeDefinition.initType.call(this, this.store, op, args)
          this.store.initializedTypes[sid] = t
        }
      }
@@ -588,14 +590,14 @@ export default function extendDatabase (Y /* :any */) {
    createType (typedefinition, id) {
      var structname = typedefinition[0].struct
      id = id || this.getNextOpId(1)
-      var op = Y.Struct[structname].create(id)
+      var op = Y.Struct[structname].create(id, typedefinition[1])
      op.type = typedefinition[0].name

-      this.requestTransaction(function * () {
+      this.requestTransaction(function () {
        if (op.id[0] === 0xFFFFFF) {
-          yield * this.setOperation(op)
+          this.setOperation(op)
        } else {
-          yield * this.applyCreatedOperations([op])
+          this.applyCreatedOperations([op])
        }
      })
      var t = Y[op.type].typeDefinition.createType(this, op, typedefinition[1])
--- a/src/Database.spec.js
+++ b/src/Database.spec.js
@@ -1,354 +0,0 @@
-/* global async, databases, describe, beforeEach, afterEach */
-/* eslint-env browser,jasmine,console */
-'use strict'
-
-var Y = require('./SpecHelper.js')
-
-for (let database of databases) {
-  describe(`Database (${database})`, function () {
-    var store
-    describe('DeleteStore', function () {
-      describe('Basic', function () {
-        beforeEach(function () {
-          store = new Y[database](null, {
-            gcTimeout: -1,
-            namespace: 'testing'
-          })
-        })
-        afterEach(function (done) {
-          store.requestTransaction(function * () {
-            yield * this.store.destroy()
-            done()
-          })
-        })
-        it('Deleted operation is deleted', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield * this.markDeleted(['u1', 10], 1)
-            expect(yield * this.isDeleted(['u1', 10])).toBeTruthy()
-            expect(yield * this.getDeleteSet()).toEqual({'u1': [[10, 1, false]]})
-            done()
-          })
-        }))
-        it('Deleted operation extends other deleted operation', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield * this.markDeleted(['u1', 10], 1)
-            yield * this.markDeleted(['u1', 11], 1)
-            expect(yield * this.isDeleted(['u1', 10])).toBeTruthy()
-            expect(yield * this.isDeleted(['u1', 11])).toBeTruthy()
-            expect(yield * this.getDeleteSet()).toEqual({'u1': [[10, 2, false]]})
-            done()
-          })
-        }))
-        it('Deleted operation extends other deleted operation', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield * this.markDeleted(['0', 3], 1)
-            yield * this.markDeleted(['0', 4], 1)
-            yield * this.markDeleted(['0', 2], 1)
-            expect(yield * this.getDeleteSet()).toEqual({'0': [[2, 3, false]]})
-            done()
-          })
-        }))
-        it('Debug #1', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield * this.markDeleted(['166', 0], 1)
-            yield * this.markDeleted(['166', 2], 1)
-            yield * this.markDeleted(['166', 0], 1)
-            yield * this.markDeleted(['166', 2], 1)
-            yield * this.markGarbageCollected(['166', 2], 1)
-            yield * this.markDeleted(['166', 1], 1)
-            yield * this.markDeleted(['166', 3], 1)
-            yield * this.markGarbageCollected(['166', 3], 1)
-            yield * this.markDeleted(['166', 0], 1)
-            expect(yield * this.getDeleteSet()).toEqual({'166': [[0, 2, false], [2, 2, true]]})
-            done()
-          })
-        }))
-        it('Debug #2', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield * this.markDeleted(['293', 0], 1)
-            yield * this.markDeleted(['291', 2], 1)
-            yield * this.markDeleted(['291', 2], 1)
-            yield * this.markGarbageCollected(['293', 0], 1)
-            yield * this.markDeleted(['293', 1], 1)
-            yield * this.markGarbageCollected(['291', 2], 1)
-            expect(yield * this.getDeleteSet()).toEqual({'291': [[2, 1, true]], '293': [[0, 1, true], [1, 1, false]]})
-            done()
-          })
-        }))
-        it('Debug #3', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield * this.markDeleted(['581', 0], 1)
-            yield * this.markDeleted(['581', 1], 1)
-            yield * this.markDeleted(['580', 0], 1)
-            yield * this.markDeleted(['580', 0], 1)
-            yield * this.markGarbageCollected(['581', 0], 1)
-            yield * this.markDeleted(['581', 2], 1)
-            yield * this.markDeleted(['580', 1], 1)
-            yield * this.markDeleted(['580', 2], 1)
-            yield * this.markDeleted(['580', 1], 1)
-            yield * this.markDeleted(['580', 2], 1)
-            yield * this.markGarbageCollected(['581', 2], 1)
-            yield * this.markGarbageCollected(['581', 1], 1)
-            yield * this.markGarbageCollected(['580', 1], 1)
-            expect(yield * this.getDeleteSet()).toEqual({'580': [[0, 1, false], [1, 1, true], [2, 1, false]], '581': [[0, 3, true]]})
-            done()
-          })
-        }))
-        it('Debug #4', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield * this.markDeleted(['544', 0], 1)
-            yield * this.markDeleted(['543', 2], 1)
-            yield * this.markDeleted(['544', 0], 1)
-            yield * this.markDeleted(['543', 2], 1)
-            yield * this.markGarbageCollected(['544', 0], 1)
-            yield * this.markDeleted(['545', 1], 1)
-            yield * this.markDeleted(['543', 4], 1)
-            yield * this.markDeleted(['543', 3], 1)
-            yield * this.markDeleted(['544', 1], 1)
-            yield * this.markDeleted(['544', 2], 1)
-            yield * this.markDeleted(['544', 1], 1)
-            yield * this.markDeleted(['544', 2], 1)
-            yield * this.markGarbageCollected(['543', 2], 1)
-            yield * this.markGarbageCollected(['543', 4], 1)
-            yield * this.markGarbageCollected(['544', 2], 1)
-            yield * this.markGarbageCollected(['543', 3], 1)
-            expect(yield * this.getDeleteSet()).toEqual({'543': [[2, 3, true]], '544': [[0, 1, true], [1, 1, false], [2, 1, true]], '545': [[1, 1, false]]})
-            done()
-          })
-        }))
-        it('Debug #5', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield * this.applyDeleteSet({'16': [[1, 2, false]], '17': [[0, 1, true], [1, 3, false]]})
-            expect(yield * this.getDeleteSet()).toEqual({'16': [[1, 2, false]], '17': [[0, 1, true], [1, 3, false]]})
-            yield * this.applyDeleteSet({'16': [[1, 2, false]], '17': [[0, 4, true]]})
-            expect(yield * this.getDeleteSet()).toEqual({'16': [[1, 2, false]], '17': [[0, 4, true]]})
-            done()
-          })
-        }))
-        it('Debug #6', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield * this.applyDeleteSet({'40': [[0, 3, false]]})
-            expect(yield * this.getDeleteSet()).toEqual({'40': [[0, 3, false]]})
-            yield * this.applyDeleteSet({'39': [[2, 2, false]], '40': [[0, 1, true], [1, 2, false]], '41': [[2, 1, false]]})
-            expect(yield * this.getDeleteSet()).toEqual({'39': [[2, 2, false]], '40': [[0, 1, true], [1, 2, false]], '41': [[2, 1, false]]})
-            done()
-          })
-        }))
-        it('Debug #7', async(function * (done) {
-          store.requestTransaction(function * () {
-            yield * this.markDeleted(['9', 2], 1)
-            yield * this.markDeleted(['11', 2], 1)
-            yield * this.markDeleted(['11', 4], 1)
-            yield * this.markDeleted(['11', 1], 1)
-            yield * this.markDeleted(['9', 4], 1)
-            yield * this.markDeleted(['10', 0], 1)
-            yield * this.markGarbageCollected(['11', 2], 1)
-            yield * this.markDeleted(['11', 2], 1)
-            yield * this.markGarbageCollected(['11', 3], 1)
-            yield * this.markDeleted(['11', 3], 1)
-            yield * this.markDeleted(['11', 3], 1)
-            yield * this.markDeleted(['9', 4], 1)
-            yield * this.markDeleted(['10', 0], 1)
-            yield * this.markGarbageCollected(['11', 1], 1)
-            yield * this.markDeleted(['11', 1], 1)
-            expect(yield * this.getDeleteSet()).toEqual({'9': [[2, 1, false], [4, 1, false]], '10': [[0, 1, false]], '11': [[1, 3, true], [4, 1, false]]})
-            done()
-          })
-        }))
-      })
-    })
-    describe('OperationStore', function () {
-      describe('Basic Tests', function () {
-        beforeEach(function () {
-          store = new Y[database](null, {
-            gcTimeout: -1,
-            namespace: 'testing'
-          })
-        })
-        afterEach(function (done) {
-          store.requestTransaction(function * () {
-            yield * this.store.destroy()
-            done()
-          })
-        })
-        it('debug #1', function (done) {
-          store.requestTransaction(function * () {
-            yield * this.os.put({id: [2]})
-            yield * this.os.put({id: [0]})
-            yield * this.os.delete([2])
-            yield * this.os.put({id: [1]})
-            expect(yield * this.os.find([0])).toBeTruthy()
-            expect(yield * this.os.find([1])).toBeTruthy()
-            expect(yield * this.os.find([2])).toBeFalsy()
-            done()
-          })
-        })
-        it('can add&retrieve 5 elements', function (done) {
-          store.requestTransaction(function * () {
-            yield * this.os.put({val: 'four', id: [4]})
-            yield * this.os.put({val: 'one', id: [1]})
-            yield * this.os.put({val: 'three', id: [3]})
-            yield * this.os.put({val: 'two', id: [2]})
-            yield * this.os.put({val: 'five', id: [5]})
-            expect((yield * this.os.find([1])).val).toEqual('one')
-            expect((yield * this.os.find([2])).val).toEqual('two')
-            expect((yield * this.os.find([3])).val).toEqual('three')
-            expect((yield * this.os.find([4])).val).toEqual('four')
-            expect((yield * this.os.find([5])).val).toEqual('five')
-            done()
-          })
-        })
-        it('5 elements do not exist anymore after deleting them', function (done) {
-          store.requestTransaction(function * () {
-            yield * this.os.put({val: 'four', id: [4]})
-            yield * this.os.put({val: 'one', id: [1]})
-            yield * this.os.put({val: 'three', id: [3]})
-            yield * this.os.put({val: 'two', id: [2]})
-            yield * this.os.put({val: 'five', id: [5]})
-            yield * this.os.delete([4])
-            expect(yield * this.os.find([4])).not.toBeTruthy()
-            yield * this.os.delete([3])
-            expect(yield * this.os.find([3])).not.toBeTruthy()
-            yield * this.os.delete([2])
-            expect(yield * this.os.find([2])).not.toBeTruthy()
-            yield * this.os.delete([1])
-            expect(yield * this.os.find([1])).not.toBeTruthy()
-            yield * this.os.delete([5])
-            expect(yield * this.os.find([5])).not.toBeTruthy()
-            done()
-          })
-        })
-      })
-      var numberOfOSTests = 1000
-      describe(`Random Tests - after adding&deleting (0.8/0.2) ${numberOfOSTests} times`, function () {
-        var elements = []
-        beforeAll(function (done) {
-          store = new Y[database](null, {
-            gcTimeout: -1,
-            namespace: 'testing'
-          })
-          store.requestTransaction(function * () {
-            for (var i = 0; i < numberOfOSTests; i++) {
-              var r = Math.random()
-              if (r < 0.8) {
-                var obj = [Math.floor(Math.random() * numberOfOSTests * 10000)]
-                if (!(yield * this.os.find(obj))) {
-                  elements.push(obj)
-                  yield * this.os.put({id: obj})
-                }
-              } else if (elements.length > 0) {
-                var elemid = Math.floor(Math.random() * elements.length)
-                var elem = elements[elemid]
-                elements = elements.filter(function (e) {
-                  return !Y.utils.compareIds(e, elem)
-                })
-                yield * this.os.delete(elem)
-              }
-            }
-            done()
-          })
-        })
-        afterAll(function (done) {
-          store.requestTransaction(function * () {
-            yield * this.store.destroy()
-            done()
-          })
-        })
-        it('can find every object', function (done) {
-          store.requestTransaction(function * () {
-            for (var id of elements) {
-              expect((yield * this.os.find(id)).id).toEqual(id)
-            }
-            done()
-          })
-        })
-
-        it('can find every object with lower bound search', function (done) {
-          store.requestTransaction(function * () {
-            for (var id of elements) {
-              var e = yield * this.os.findWithLowerBound(id)
-              expect(e.id).toEqual(id)
-            }
-            done()
-          })
-        })
-
-        it('iterating over a tree with lower bound yields the right amount of results', function (done) {
-          var lowerBound = elements[Math.floor(Math.random() * elements.length)]
-          var expectedResults = elements.filter(function (e, pos) {
-            return (Y.utils.smaller(lowerBound, e) || Y.utils.compareIds(e, lowerBound)) && elements.indexOf(e) === pos
-          }).length
-
-          var actualResults = 0
-          store.requestTransaction(function * () {
-            yield * this.os.iterate(this, lowerBound, null, function * (val) {
-              expect(val).toBeDefined()
-              actualResults++
-            })
-            expect(expectedResults).toEqual(actualResults)
-            done()
-          })
-        })
-
-        it('iterating over a tree without bounds yield the right amount of results', function (done) {
-          var lowerBound = null
-          var expectedResults = elements.filter(function (e, pos) {
-            return elements.indexOf(e) === pos
-          }).length
-          var actualResults = 0
-          store.requestTransaction(function * () {
-            yield * this.os.iterate(this, lowerBound, null, function * (val) {
-              expect(val).toBeDefined()
-              actualResults++
-            })
-            expect(expectedResults).toEqual(actualResults)
-            done()
-          })
-        })
-
-        it('iterating over a tree with upper bound yields the right amount of results', function (done) {
-          var upperBound = elements[Math.floor(Math.random() * elements.length)]
-          var expectedResults = elements.filter(function (e, pos) {
-            return (Y.utils.smaller(e, upperBound) || Y.utils.compareIds(e, upperBound)) && elements.indexOf(e) === pos
-          }).length
-
-          var actualResults = 0
-          store.requestTransaction(function * () {
-            yield * this.os.iterate(this, null, upperBound, function * (val) {
-              expect(val).toBeDefined()
-              actualResults++
-            })
-            expect(expectedResults).toEqual(actualResults)
-            done()
-          })
-        })
-
-        it('iterating over a tree with upper and lower bounds yield the right amount of results', function (done) {
-          var b1 = elements[Math.floor(Math.random() * elements.length)]
-          var b2 = elements[Math.floor(Math.random() * elements.length)]
-          var upperBound, lowerBound
-          if (Y.utils.smaller(b1, b2)) {
-            lowerBound = b1
-            upperBound = b2
-          } else {
-            lowerBound = b2
-            upperBound = b1
-          }
-          var expectedResults = elements.filter(function (e, pos) {
-            return (Y.utils.smaller(lowerBound, e) || Y.utils.compareIds(e, lowerBound)) &&
-              (Y.utils.smaller(e, upperBound) || Y.utils.compareIds(e, upperBound)) && elements.indexOf(e) === pos
-          }).length
-          var actualResults = 0
-          store.requestTransaction(function * () {
-            yield * this.os.iterate(this, lowerBound, upperBound, function * (val) {
-              expect(val).toBeDefined()
-              actualResults++
-            })
-            expect(expectedResults).toEqual(actualResults)
-            done()
-          })
-        })
-      })
-    })
-  })
-}
--- a/src/Encoding.js
+++ b/src/Encoding.js
@@ -8,6 +8,10 @@ export class BinaryEncoder {
    this.data = []
  }

+  get length () {
+    return this.data.length
+  }
+
  get pos () {
    return this.data.length
  }
--- a/src/MessageHandler.js
+++ b/src/MessageHandler.js
@@ -58,7 +58,7 @@ export function computeMessageUpdate (decoder, encoder, conn) {
 }

 export function sendSyncStep1 (conn, syncUser) {
-  conn.y.db.requestTransaction(function * () {
+  conn.y.db.requestTransaction(function () {
    let encoder = new BinaryEncoder()
    encoder.writeVarString(conn.opts.room || '')
    encoder.writeVarString('sync step 1')
@@ -66,7 +66,7 @@ export function sendSyncStep1 (conn, syncUser) {
    encoder.writeVarUint(conn.protocolVersion)
    let preferUntransformed = conn.preferUntransformed && this.os.length === 0 // TODO: length may not be defined
    encoder.writeUint8(preferUntransformed ? 1 : 0)
-    yield * this.writeStateSet(encoder)
+    this.writeStateSet(encoder)
    conn.send(syncUser, encoder.createBuffer())
  })
 }
@@ -99,19 +99,19 @@ export function computeMessageSyncStep1 (decoder, encoder, conn, senderConn, sen

  return conn.y.db.whenTransactionsFinished().then(() => {
    // send sync step 2
-    conn.y.db.requestTransaction(function * () {
+    conn.y.db.requestTransaction(function () {
      encoder.writeVarString('sync step 2')
      encoder.writeVarString(conn.authInfo || '')

      if (preferUntransformed) {
        encoder.writeUint8(1)
-        yield * this.writeOperationsUntransformed(encoder)
+        this.writeOperationsUntransformed(encoder)
      } else {
        encoder.writeUint8(0)
-        yield * this.writeOperations(encoder, decoder)
+        this.writeOperations(encoder, decoder)
      }

-      yield * this.writeDeleteSet(encoder)
+      this.writeDeleteSet(encoder)
      conn.send(senderConn.uid, encoder.createBuffer())
      senderConn.receivedSyncStep2 = true
    })
@@ -174,17 +174,17 @@ export function computeMessageSyncStep2 (decoder, encoder, conn, senderConn, sen
  let defer = senderConn.syncStep2

  // apply operations first
-  db.requestTransaction(function * () {
+  db.requestTransaction(function () {
    let osUntransformed = decoder.readUint8()
    if (osUntransformed === 1) {
-      yield * this.applyOperationsUntransformed(decoder)
+      this.applyOperationsUntransformed(decoder)
    } else {
      this.store.applyOperations(decoder)
    }
  })
  // then apply ds
-  db.requestTransaction(function * () {
-    yield * this.applyDeleteSet(decoder)
+  db.requestTransaction(function () {
+    this.applyDeleteSet(decoder)
  })
  return db.whenTransactionsFinished().then(() => {
    conn._setSyncedWith(sender)
--- a/src/Persistence.js
+++ b/src/Persistence.js
@@ -8,9 +8,11 @@ export default function extendPersistence (Y) {
      this.saveOperationsBuffer = []
      this.log = Y.debug('y:persistence')
    }
+
    saveToMessageQueue (binary) {
      this.log('Room %s: Save message to message queue', this.y.options.connector.room)
    }
+
    saveOperations (ops) {
      ops = ops.map(function (op) {
        return Y.Struct[op.struct].encode(op)
@@ -39,5 +41,6 @@ export default function extendPersistence (Y) {
      }
    }
  }
+
  Y.AbstractPersistence = AbstractPersistence
 }
--- a/src/RedBlackTree.js
+++ b/src/RedBlackTree.js
@@ -0,0 +1,506 @@
+
+export default function extendRBTree (Y) {
+  class N {
+    // A created node is always red!
+    constructor (val) {
+      this.val = val
+      this.color = true
+      this._left = null
+      this._right = null
+      this._parent = null
+      if (val.id === null) {
+        throw new Error('You must define id!')
+      }
+    }
+    isRed () { return this.color }
+    isBlack () { return !this.color }
+    redden () { this.color = true; return this }
+    blacken () { this.color = false; return this }
+    get grandparent () {
+      return this.parent.parent
+    }
+    get parent () {
+      return this._parent
+    }
+    get sibling () {
+      return (this === this.parent.left)
+        ? this.parent.right : this.parent.left
+    }
+    get left () {
+      return this._left
+    }
+    get right () {
+      return this._right
+    }
+    set left (n) {
+      if (n !== null) {
+        n._parent = this
+      }
+      this._left = n
+    }
+    set right (n) {
+      if (n !== null) {
+        n._parent = this
+      }
+      this._right = n
+    }
+    rotateLeft (tree) {
+      var parent = this.parent
+      var newParent = this.right
+      var newRight = this.right.left
+      newParent.left = this
+      this.right = newRight
+      if (parent === null) {
+        tree.root = newParent
+        newParent._parent = null
+      } else if (parent.left === this) {
+        parent.left = newParent
+      } else if (parent.right === this) {
+        parent.right = newParent
+      } else {
+        throw new Error('The elements are wrongly connected!')
+      }
+    }
+    next () {
+      if (this.right !== null) {
+        // search the most left node in the right tree
+        var o = this.right
+        while (o.left !== null) {
+          o = o.left
+        }
+        return o
+      } else {
+        var p = this
+        while (p.parent !== null && p !== p.parent.left) {
+          p = p.parent
+        }
+        return p.parent
+      }
+    }
+    prev () {
+      if (this.left !== null) {
+        // search the most right node in the left tree
+        var o = this.left
+        while (o.right !== null) {
+          o = o.right
+        }
+        return o
+      } else {
+        var p = this
+        while (p.parent !== null && p !== p.parent.right) {
+          p = p.parent
+        }
+        return p.parent
+      }
+    }
+    rotateRight (tree) {
+      var parent = this.parent
+      var newParent = this.left
+      var newLeft = this.left.right
+      newParent.right = this
+      this.left = newLeft
+      if (parent === null) {
+        tree.root = newParent
+        newParent._parent = null
+      } else if (parent.left === this) {
+        parent.left = newParent
+      } else if (parent.right === this) {
+        parent.right = newParent
+      } else {
+        throw new Error('The elements are wrongly connected!')
+      }
+    }
+    getUncle () {
+      // we can assume that grandparent exists when this is called!
+      if (this.parent === this.parent.parent.left) {
+        return this.parent.parent.right
+      } else {
+        return this.parent.parent.left
+      }
+    }
+  }
+
+  class RBTree {
+    constructor () {
+      this.root = null
+      this.length = 0
+    }
+    findNext (id) {
+      return this.findWithLowerBound([id[0], id[1] + 1])
+    }
+    findPrev (id) {
+      return this.findWithUpperBound([id[0], id[1] - 1])
+    }
+    findNodeWithLowerBound (from) {
+      if (from === void 0) {
+        throw new Error('You must define from!')
+      }
+      var o = this.root
+      if (o === null) {
+        return null
+      } else {
+        while (true) {
+          if ((from === null || Y.utils.smaller(from, o.val.id)) && o.left !== null) {
+            // o is included in the bound
+            // try to find an element that is closer to the bound
+            o = o.left
+          } else if (from !== null && Y.utils.smaller(o.val.id, from)) {
+            // o is not within the bound, maybe one of the right elements is..
+            if (o.right !== null) {
+              o = o.right
+            } else {
+              // there is no right element. Search for the next bigger element,
+              // this should be within the bounds
+              return o.next()
+            }
+          } else {
+            return o
+          }
+        }
+      }
+    }
+    findNodeWithUpperBound (to) {
+      if (to === void 0) {
+        throw new Error('You must define from!')
+      }
+      var o = this.root
+      if (o === null) {
+        return null
+      } else {
+        while (true) {
+          if ((to === null || Y.utils.smaller(o.val.id, to)) && o.right !== null) {
+            // o is included in the bound
+            // try to find an element that is closer to the bound
+            o = o.right
+          } else if (to !== null && Y.utils.smaller(to, o.val.id)) {
+            // o is not within the bound, maybe one of the left elements is..
+            if (o.left !== null) {
+              o = o.left
+            } else {
+              // there is no left element. Search for the prev smaller element,
+              // this should be within the bounds
+              return o.prev()
+            }
+          } else {
+            return o
+          }
+        }
+      }
+    }
+    findSmallestNode () {
+      var o = this.root
+      while (o != null && o.left != null) {
+        o = o.left
+      }
+      return o
+    }
+    findWithLowerBound (from) {
+      var n = this.findNodeWithLowerBound(from)
+      return n == null ? null : n.val
+    }
+    findWithUpperBound (to) {
+      var n = this.findNodeWithUpperBound(to)
+      return n == null ? null : n.val
+    }
+    iterate (t, from, to, f) {
+      var o
+      if (from === null) {
+        o = this.findSmallestNode()
+      } else {
+        o = this.findNodeWithLowerBound(from)
+      }
+      while (
+        o !== null &&
+        (
+          to === null || // eslint-disable-line no-unmodified-loop-condition
+          Y.utils.smaller(o.val.id, to) ||
+          Y.utils.compareIds(o.val.id, to)
+        )
+      ) {
+        f.call(t, o.val)
+        o = o.next()
+      }
+      return true
+    }
+    logTable (from, to, filter) {
+      if (filter == null) {
+        filter = function () {
+          return true
+        }
+      }
+      if (from == null) { from = null }
+      if (to == null) { to = null }
+      var os = []
+      this.iterate(this, from, to, function (o) {
+        if (filter(o)) {
+          var o_ = {}
+          for (var key in o) {
+            if (typeof o[key] === 'object') {
+              o_[key] = JSON.stringify(o[key])
+            } else {
+              o_[key] = o[key]
+            }
+          }
+          os.push(o_)
+        }
+      })
+      if (console.table != null) {
+        console.table(os)
+      }
+    }
+    find (id) {
+      var n
+      return (n = this.findNode(id)) ? n.val : null
+    }
+    findNode (id) {
+      if (id == null || id.constructor !== Array) {
+        throw new Error('Expect id to be an array!')
+      }
+      var o = this.root
+      if (o === null) {
+        return false
+      } else {
+        while (true) {
+          if (o === null) {
+            return false
+          }
+          if (Y.utils.smaller(id, o.val.id)) {
+            o = o.left
+          } else if (Y.utils.smaller(o.val.id, id)) {
+            o = o.right
+          } else {
+            return o
+          }
+        }
+      }
+    }
+    delete (id) {
+      if (id == null || id.constructor !== Array) {
+        throw new Error('id is expected to be an Array!')
+      }
+      var d = this.findNode(id)
+      if (d == null) {
+        // throw new Error('Element does not exist!')
+        return
+      }
+      this.length--
+      if (d.left !== null && d.right !== null) {
+        // switch d with the greates element in the left subtree.
+        // o should have at most one child.
+        var o = d.left
+        // find
+        while (o.right !== null) {
+          o = o.right
+        }
+        // switch
+        d.val = o.val
+        d = o
+      }
+      // d has at most one child
+      // let n be the node that replaces d
+      var isFakeChild
+      var child = d.left || d.right
+      if (child === null) {
+        isFakeChild = true
+        child = new N({id: 0})
+        child.blacken()
+        d.right = child
+      } else {
+        isFakeChild = false
+      }
+
+      if (d.parent === null) {
+        if (!isFakeChild) {
+          this.root = child
+          child.blacken()
+          child._parent = null
+        } else {
+          this.root = null
+        }
+        return
+      } else if (d.parent.left === d) {
+        d.parent.left = child
+      } else if (d.parent.right === d) {
+        d.parent.right = child
+      } else {
+        throw new Error('Impossible!')
+      }
+      if (d.isBlack()) {
+        if (child.isRed()) {
+          child.blacken()
+        } else {
+          this._fixDelete(child)
+        }
+      }
+      this.root.blacken()
+      if (isFakeChild) {
+        if (child.parent.left === child) {
+          child.parent.left = null
+        } else if (child.parent.right === child) {
+          child.parent.right = null
+        } else {
+          throw new Error('Impossible #3')
+        }
+      }
+    }
+    _fixDelete (n) {
+      function isBlack (node) {
+        return node !== null ? node.isBlack() : true
+      }
+      function isRed (node) {
+        return node !== null ? node.isRed() : false
+      }
+      if (n.parent === null) {
+        // this can only be called after the first iteration of fixDelete.
+        return
+      }
+      // d was already replaced by the child
+      // d is not the root
+      // d and child are black
+      var sibling = n.sibling
+      if (isRed(sibling)) {
+        // make sibling the grandfather
+        n.parent.redden()
+        sibling.blacken()
+        if (n === n.parent.left) {
+          n.parent.rotateLeft(this)
+        } else if (n === n.parent.right) {
+          n.parent.rotateRight(this)
+        } else {
+          throw new Error('Impossible #2')
+        }
+        sibling = n.sibling
+      }
+      // parent, sibling, and children of n are black
+      if (n.parent.isBlack() &&
+        sibling.isBlack() &&
+        isBlack(sibling.left) &&
+        isBlack(sibling.right)
+      ) {
+        sibling.redden()
+        this._fixDelete(n.parent)
+      } else if (n.parent.isRed() &&
+        sibling.isBlack() &&
+        isBlack(sibling.left) &&
+        isBlack(sibling.right)
+      ) {
+        sibling.redden()
+        n.parent.blacken()
+      } else {
+        if (n === n.parent.left &&
+          sibling.isBlack() &&
+          isRed(sibling.left) &&
+          isBlack(sibling.right)
+        ) {
+          sibling.redden()
+          sibling.left.blacken()
+          sibling.rotateRight(this)
+          sibling = n.sibling
+        } else if (n === n.parent.right &&
+          sibling.isBlack() &&
+          isRed(sibling.right) &&
+          isBlack(sibling.left)
+        ) {
+          sibling.redden()
+          sibling.right.blacken()
+          sibling.rotateLeft(this)
+          sibling = n.sibling
+        }
+        sibling.color = n.parent.color
+        n.parent.blacken()
+        if (n === n.parent.left) {
+          sibling.right.blacken()
+          n.parent.rotateLeft(this)
+        } else {
+          sibling.left.blacken()
+          n.parent.rotateRight(this)
+        }
+      }
+    }
+    put (v) {
+      if (v == null || v.id == null || v.id.constructor !== Array) {
+        throw new Error('v is expected to have an id property which is an Array!')
+      }
+      var node = new N(v)
+      if (this.root !== null) {
+        var p = this.root // p abbrev. parent
+        while (true) {
+          if (Y.utils.smaller(node.val.id, p.val.id)) {
+            if (p.left === null) {
+              p.left = node
+              break
+            } else {
+              p = p.left
+            }
+          } else if (Y.utils.smaller(p.val.id, node.val.id)) {
+            if (p.right === null) {
+              p.right = node
+              break
+            } else {
+              p = p.right
+            }
+          } else {
+            p.val = node.val
+            return p
+          }
+        }
+        this._fixInsert(node)
+      } else {
+        this.root = node
+      }
+      this.length++
+      this.root.blacken()
+      return node
+    }
+    _fixInsert (n) {
+      if (n.parent === null) {
+        n.blacken()
+        return
+      } else if (n.parent.isBlack()) {
+        return
+      }
+      var uncle = n.getUncle()
+      if (uncle !== null && uncle.isRed()) {
+        // Note: parent: red, uncle: red
+        n.parent.blacken()
+        uncle.blacken()
+        n.grandparent.redden()
+        this._fixInsert(n.grandparent)
+      } else {
+        // Note: parent: red, uncle: black or null
+        // Now we transform the tree in such a way that
+        // either of these holds:
+        //   1) grandparent.left.isRed
+        //     and grandparent.left.left.isRed
+        //   2) grandparent.right.isRed
+        //     and grandparent.right.right.isRed
+        if (n === n.parent.right && n.parent === n.grandparent.left) {
+          n.parent.rotateLeft(this)
+          // Since we rotated and want to use the previous
+          // cases, we need to set n in such a way that
+          // n.parent.isRed again
+          n = n.left
+        } else if (n === n.parent.left && n.parent === n.grandparent.right) {
+          n.parent.rotateRight(this)
+          // see above
+          n = n.right
+        }
+        // Case 1) or 2) hold from here on.
+        // Now traverse grandparent, make parent a black node
+        // on the highest level which holds two red nodes.
+        n.parent.blacken()
+        n.grandparent.redden()
+        if (n === n.parent.left) {
+          // Case 1
+          n.grandparent.rotateRight(this)
+        } else {
+          // Case 2
+          n.grandparent.rotateLeft(this)
+        }
+      }
+    }
+    flush () {}
+  }
+
+  Y.utils.RBTree = RBTree
+}
--- a/src/Struct.js
+++ b/src/Struct.js
--- a/src/Transaction.js
+++ b/src/Transaction.js
@@ -86,11 +86,11 @@ export default function extendTransaction (Y) {
        * does not check for Struct.*.requiredOps()
        * also broadcasts it through the connector
    */
-    * applyCreatedOperations (ops) {
+    applyCreatedOperations (ops) {
      var send = []
      for (var i = 0; i < ops.length; i++) {
        var op = ops[i]
-        yield * this.store.tryExecute.call(this, op)
+        this.store.tryExecute.call(this, op)
        if (op.id == null || typeof op.id[1] !== 'string') {
          send.push(Y.Struct[op.struct].encode(op))
        }
@@ -104,17 +104,17 @@ export default function extendTransaction (Y) {
      }
    }

-    * deleteList (start) {
+    deleteList (start) {
      while (start != null) {
-        start = yield * this.getOperation(start)
+        start = this.getOperation(start)
        if (!start.gc) {
          start.gc = true
          start.deleted = true
-          yield * this.setOperation(start)
+          this.setOperation(start)
          var delLength = start.content != null ? start.content.length : 1
-          yield * this.markDeleted(start.id, delLength)
+          this.markDeleted(start.id, delLength)
          if (start.opContent != null) {
-            yield * this.deleteOperation(start.opContent)
+            this.deleteOperation(start.opContent)
          }
          this.store.queueGarbageCollector(start.id)
        }
@@ -125,14 +125,14 @@ export default function extendTransaction (Y) {
    /*
      Mark an operation as deleted, and add it to the GC, if possible.
    */
-    * deleteOperation (targetId, length, preventCallType) /* :Generator<any, any, any> */ {
+    deleteOperation (targetId, length, preventCallType) /* :Generator<any, any, any> */ {
      if (length == null) {
        length = 1
      }
-      yield * this.markDeleted(targetId, length)
+      this.markDeleted(targetId, length)
      while (length > 0) {
        var callType = false
-        var target = yield * this.os.findWithUpperBound([targetId[0], targetId[1] + length - 1])
+        var target = this.os.findWithUpperBound([targetId[0], targetId[1] + length - 1])
        var targetLength = target != null && target.content != null ? target.content.length : 1
        if (target == null || target.id[0] !== targetId[0] || target.id[1] + targetLength <= targetId[1]) {
          // does not exist or is not in the range of the deletion
@@ -143,12 +143,12 @@ export default function extendTransaction (Y) {
          if (!target.deleted) {
            if (target.id[1] < targetId[1]) {
              // starts to the left of the deletion range
-              target = yield * this.getInsertionCleanStart(targetId)
+              target = this.getInsertionCleanStart(targetId)
              targetLength = target.content.length // must have content property!
            }
            if (target.id[1] + targetLength > targetId[1] + length) {
              // ends to the right of the deletion range
-              target = yield * this.getInsertionCleanEnd([targetId[0], targetId[1] + length - 1])
+              target = this.getInsertionCleanEnd([targetId[0], targetId[1] + length - 1])
              targetLength = target.content.length
            }
          }
@@ -163,35 +163,35 @@ export default function extendTransaction (Y) {
            // delete containing lists
            if (target.start != null) {
              // TODO: don't do it like this .. -.-
-              yield * this.deleteList(target.start)
-              // yield * this.deleteList(target.id) -- do not gc itself because this may still get referenced
+              this.deleteList(target.start)
+              // this.deleteList(target.id) -- do not gc itself because this may still get referenced
            }
            if (target.map != null) {
              for (var name in target.map) {
-                yield * this.deleteList(target.map[name])
+                this.deleteList(target.map[name])
              }
              // TODO: here to..  (see above)
-              // yield * this.deleteList(target.id) -- see above
+              // this.deleteList(target.id) -- see above
            }
            if (target.opContent != null) {
-              yield * this.deleteOperation(target.opContent)
+              this.deleteOperation(target.opContent)
              // target.opContent = null
            }
            if (target.requires != null) {
              for (var i = 0; i < target.requires.length; i++) {
-                yield * this.deleteOperation(target.requires[i])
+                this.deleteOperation(target.requires[i])
              }
            }
          }
          var left
          if (target.left != null) {
-            left = yield * this.getInsertion(target.left)
+            left = this.getInsertion(target.left)
          } else {
            left = null
          }

          // set here because it was deleted and/or gc'd
-          yield * this.setOperation(target)
+          this.setOperation(target)

          /*
            Check if it is possible to add right to the gc.
@@ -200,12 +200,12 @@ export default function extendTransaction (Y) {
          */
          var right
          if (target.right != null) {
-            right = yield * this.getOperation(target.right)
+            right = this.getOperation(target.right)
          } else {
            right = null
          }
          if (callType && !preventCallType) {
-            yield * this.store.operationAdded(this, {
+            this.store.operationAdded(this, {
              struct: 'Delete',
              target: target.id,
              length: targetLength,
@@ -213,9 +213,9 @@ export default function extendTransaction (Y) {
            })
          }
          // need to gc in the end!
-          yield * this.store.addToGarbageCollector.call(this, target, left)
+          this.store.addToGarbageCollector.call(this, target, left)
          if (right != null) {
-            yield * this.store.addToGarbageCollector.call(this, right, target)
+            this.store.addToGarbageCollector.call(this, right, target)
          }
        }
      }
@@ -223,25 +223,25 @@ export default function extendTransaction (Y) {
    /*
      Mark an operation as deleted&gc'd
    */
-    * markGarbageCollected (id, len) {
+    markGarbageCollected (id, len) {
      // this.mem.push(["gc", id]);
-      this.store.addToDebug('yield * this.markGarbageCollected(', id, ', ', len, ')')
-      var n = yield * this.markDeleted(id, len)
+      this.store.addToDebug('this.markGarbageCollected(', id, ', ', len, ')')
+      var n = this.markDeleted(id, len)
      if (n.id[1] < id[1] && !n.gc) {
        // un-extend left
        var newlen = n.len - (id[1] - n.id[1])
        n.len -= newlen
-        yield * this.ds.put(n)
+        this.ds.put(n)
        n = {id: id, len: newlen, gc: false}
-        yield * this.ds.put(n)
+        this.ds.put(n)
      }
      // get prev&next before adding a new operation
-      var prev = yield * this.ds.findPrev(id)
-      var next = yield * this.ds.findNext(id)
+      var prev = this.ds.findPrev(id)
+      var next = this.ds.findNext(id)

      if (id[1] + len < n.id[1] + n.len && !n.gc) {
        // un-extend right
-        yield * this.ds.put({id: [id[0], id[1] + len], len: n.len - len, gc: false})
+        this.ds.put({id: [id[0], id[1] + len], len: n.len - len, gc: false})
        n.len = len
      }
      // set gc'd
@@ -253,7 +253,7 @@ export default function extendTransaction (Y) {
        Y.utils.compareIds([prev.id[0], prev.id[1] + prev.len], n.id)
      ) {
        prev.len += n.len
-        yield * this.ds.delete(n.id)
+        this.ds.delete(n.id)
        n = prev
        // ds.put n here?
      }
@@ -264,22 +264,22 @@ export default function extendTransaction (Y) {
        Y.utils.compareIds([n.id[0], n.id[1] + n.len], next.id)
      ) {
        n.len += next.len
-        yield * this.ds.delete(next.id)
+        this.ds.delete(next.id)
      }
-      yield * this.ds.put(n)
-      yield * this.updateState(n.id[0])
+      this.ds.put(n)
+      this.updateState(n.id[0])
    }
    /*
      Mark an operation as deleted.

      returns the delete node
    */
-    * markDeleted (id, length) {
+    markDeleted (id, length) {
      if (length == null) {
        length = 1
      }
      // this.mem.push(["del", id]);
-      var n = yield * this.ds.findWithUpperBound(id)
+      var n = this.ds.findWithUpperBound(id)
      if (n != null && n.id[0] === id[0]) {
        if (n.id[1] <= id[1] && id[1] <= n.id[1] + n.len) {
          // id is in n's range
@@ -293,7 +293,7 @@ export default function extendTransaction (Y) {
              if (diff < length) {
                // a partial deletion
                n = {id: [id[0], id[1] + diff], len: length - diff, gc: false}
-                yield * this.ds.put(n)
+                this.ds.put(n)
              } else {
                // already gc'd
                throw new Error(
@@ -308,15 +308,15 @@ export default function extendTransaction (Y) {
        } else {
          // cannot extend left (there is no left!)
          n = {id: id, len: length, gc: false}
-          yield * this.ds.put(n) // TODO: you double-put !!
+          this.ds.put(n) // TODO: you double-put !!
        }
      } else {
        // cannot extend left
        n = {id: id, len: length, gc: false}
-        yield * this.ds.put(n)
+        this.ds.put(n)
      }
      // can extend right?
-      var next = yield * this.ds.findNext(n.id)
+      var next = this.ds.findNext(n.id)
      if (
        next != null &&
        n.id[0] === next.id[0] &&
@@ -332,8 +332,8 @@ export default function extendTransaction (Y) {
              // delete the missing range after next
              diff = diff - next.len // missing range after next
              if (diff > 0) {
-                yield * this.ds.put(n) // unneccessary? TODO!
-                yield * this.markDeleted([next.id[0], next.id[1] + next.len], diff)
+                this.ds.put(n) // unneccessary? TODO!
+                this.markDeleted([next.id[0], next.id[1] + next.len], diff)
              }
            }
            break
@@ -342,8 +342,8 @@ export default function extendTransaction (Y) {
            if (diff > next.len) {
              // n is even longer than next
              // get next.next, and try to extend it
-              var _next = yield * this.ds.findNext(next.id)
-              yield * this.ds.delete(next.id)
+              var _next = this.ds.findNext(next.id)
+              this.ds.delete(next.id)
              if (_next == null || n.id[0] !== _next.id[0]) {
                break
              } else {
@@ -354,13 +354,13 @@ export default function extendTransaction (Y) {
            } else {
              // n just partially overlaps with next. extend n, delete next, and break this loop
              n.len += next.len - diff
-              yield * this.ds.delete(next.id)
+              this.ds.delete(next.id)
              break
            }
          }
        }
      }
-      yield * this.ds.put(n)
+      this.ds.put(n)
      return n
    }
    /*
@@ -368,7 +368,7 @@ export default function extendTransaction (Y) {
      other clients (e.g. master). This will query the database for
      operations that can be gc'd and add them to the garbage collector.
    */
-    * garbageCollectAfterSync () {
+    garbageCollectAfterSync () {
      // debugger
      if (this.store.gc1.length > 0 || this.store.gc2.length > 0) {
        console.warn('gc should be empty after sync')
@@ -376,28 +376,28 @@ export default function extendTransaction (Y) {
      if (!this.store.gc) {
        return
      }
-      yield * this.os.iterate(this, null, null, function * (op) {
+      this.os.iterate(this, null, null, function (op) {
        if (op.gc) {
          delete op.gc
-          yield * this.setOperation(op)
+          this.setOperation(op)
        }
        if (op.parent != null) {
-          var parentDeleted = yield * this.isDeleted(op.parent)
+          var parentDeleted = this.isDeleted(op.parent)
          if (parentDeleted) {
            op.gc = true
            if (!op.deleted) {
-              yield * this.markDeleted(op.id, op.content != null ? op.content.length : 1)
+              this.markDeleted(op.id, op.content != null ? op.content.length : 1)
              op.deleted = true
              if (op.opContent != null) {
-                yield * this.deleteOperation(op.opContent)
+                this.deleteOperation(op.opContent)
              }
              if (op.requires != null) {
                for (var i = 0; i < op.requires.length; i++) {
-                  yield * this.deleteOperation(op.requires[i])
+                  this.deleteOperation(op.requires[i])
                }
              }
            }
-            yield * this.setOperation(op)
+            this.setOperation(op)
            this.store.gc1.push(op.id) // this is ok becaues its shortly before sync (otherwise use queueGarbageCollector!)
            return
          }
@@ -405,9 +405,9 @@ export default function extendTransaction (Y) {
        if (op.deleted) {
          var left = null
          if (op.left != null) {
-            left = yield * this.getInsertion(op.left)
+            left = this.getInsertion(op.left)
          }
-          yield * this.store.addToGarbageCollector.call(this, op, left)
+          this.store.addToGarbageCollector.call(this, op, left)
        }
      })
    }
@@ -420,10 +420,10 @@ export default function extendTransaction (Y) {
      * reset parent.end
      * reset origins of all right ops
    */
-    * garbageCollectOperation (id) {
-      this.store.addToDebug('yield * this.garbageCollectOperation(', id, ')')
-      var o = yield * this.getOperation(id)
-      yield * this.markGarbageCollected(id, (o != null && o.content != null) ? o.content.length : 1) // always mark gc'd
+    garbageCollectOperation (id) {
+      this.store.addToDebug('this.garbageCollectOperation(', id, ')')
+      var o = this.getOperation(id)
+      this.markGarbageCollected(id, (o != null && o.content != null) ? o.content.length : 1) // always mark gc'd
      // if op exists, then clean that mess up..
      if (o != null) {
        var deps = []
@@ -434,32 +434,32 @@ export default function extendTransaction (Y) {
          deps = deps.concat(o.requires)
        }
        for (var i = 0; i < deps.length; i++) {
-          var dep = yield * this.getOperation(deps[i])
+          var dep = this.getOperation(deps[i])
          if (dep != null) {
            if (!dep.deleted) {
-              yield * this.deleteOperation(dep.id)
-              dep = yield * this.getOperation(dep.id)
+              this.deleteOperation(dep.id)
+              dep = this.getOperation(dep.id)
            }
            dep.gc = true
-            yield * this.setOperation(dep)
+            this.setOperation(dep)
            this.store.queueGarbageCollector(dep.id)
          } else {
-            yield * this.markGarbageCollected(deps[i], 1)
+            this.markGarbageCollected(deps[i], 1)
          }
        }

        // remove gc'd op from the left op, if it exists
        if (o.left != null) {
-          var left = yield * this.getInsertion(o.left)
+          var left = this.getInsertion(o.left)
          left.right = o.right
-          yield * this.setOperation(left)
+          this.setOperation(left)
        }
        // remove gc'd op from the right op, if it exists
        // also reset origins of right ops
        if (o.right != null) {
-          var right = yield * this.getOperation(o.right)
+          var right = this.getOperation(o.right)
          right.left = o.left
-          yield * this.setOperation(right)
+          this.setOperation(right)

          if (o.originOf != null && o.originOf.length > 0) {
            // find new origin of right ops
@@ -478,7 +478,7 @@ export default function extendTransaction (Y) {
            right.origin = neworigin
            // search until you find origin pointer to the left of o
            if (right.right != null) {
-              var i = yield * this.getOperation(right.right)
+              var i = this.getOperation(right.right)
              var ids = [o.id, o.right]
              while (ids.some(function (id) {
                return Y.utils.compareIds(id, i.origin)
@@ -486,14 +486,14 @@ export default function extendTransaction (Y) {
                if (Y.utils.compareIds(i.origin, o.id)) {
                  // reset origin of i
                  i.origin = neworigin
-                  yield * this.setOperation(i)
+                  this.setOperation(i)
                }
                // get next i
                if (i.right == null) {
                  break
                } else {
                  ids.push(i.id)
-                  i = yield * this.getOperation(i.right)
+                  i = this.getOperation(i.right)
                }
              }
            }
@@ -502,20 +502,20 @@ export default function extendTransaction (Y) {
            // ** Now the new implementation starts **
            // reset neworigin of all originOf[*]
            for (var _i in o.originOf) {
-              var originsIn = yield * this.getOperation(o.originOf[_i])
+              var originsIn = this.getOperation(o.originOf[_i])
              if (originsIn != null) {
                originsIn.origin = neworigin
-                yield * this.setOperation(originsIn)
+                this.setOperation(originsIn)
              }
            }
            if (neworigin != null) {
-              var neworigin_ = yield * this.getInsertion(neworigin)
+              var neworigin_ = this.getInsertion(neworigin)
              if (neworigin_.originOf == null) {
                neworigin_.originOf = o.originOf
              } else {
                neworigin_.originOf = o.originOf.concat(neworigin_.originOf)
              }
-              yield * this.setOperation(neworigin_)
+              this.setOperation(neworigin_)
            }
            // we don't need to set right here, because
            // right should be in o.originOf => it is set it the previous for loop
@@ -524,15 +524,15 @@ export default function extendTransaction (Y) {
        // o may originate in another operation.
        // Since o is deleted, we have to reset o.origin's `originOf` property
        if (o.origin != null) {
-          var origin = yield * this.getInsertion(o.origin)
+          var origin = this.getInsertion(o.origin)
          origin.originOf = origin.originOf.filter(function (_id) {
            return !Y.utils.compareIds(id, _id)
          })
-          yield * this.setOperation(origin)
+          this.setOperation(origin)
        }
        var parent
        if (o.parent != null) {
-          parent = yield * this.getOperation(o.parent)
+          parent = this.getOperation(o.parent)
        }
        // remove gc'd op from parent, if it exists
        if (parent != null) {
@@ -559,38 +559,38 @@ export default function extendTransaction (Y) {
            }
          }
          if (setParent) {
-            yield * this.setOperation(parent)
+            this.setOperation(parent)
          }
        }
        // finally remove it from the os
-        yield * this.removeOperation(o.id)
+        this.removeOperation(o.id)
      }
    }
-    * checkDeleteStoreForState (state) {
-      var n = yield * this.ds.findWithUpperBound([state.user, state.clock])
+    checkDeleteStoreForState (state) {
+      var n = this.ds.findWithUpperBound([state.user, state.clock])
      if (n != null && n.id[0] === state.user && n.gc) {
        state.clock = Math.max(state.clock, n.id[1] + n.len)
      }
    }
-    * updateState (user) {
-      var state = yield * this.getState(user)
-      yield * this.checkDeleteStoreForState(state)
-      var o = yield * this.getInsertion([user, state.clock])
+    updateState (user) {
+      var state = this.getState(user)
+      this.checkDeleteStoreForState(state)
+      var o = this.getInsertion([user, state.clock])
      var oLength = (o != null && o.content != null) ? o.content.length : 1
      while (o != null && user === o.id[0] && o.id[1] <= state.clock && o.id[1] + oLength > state.clock) {
        // either its a new operation (1. case), or it is an operation that was deleted, but is not yet in the OS
        state.clock += oLength
-        yield * this.checkDeleteStoreForState(state)
-        o = yield * this.os.findNext(o.id)
+        this.checkDeleteStoreForState(state)
+        o = this.os.findNext(o.id)
        oLength = (o != null && o.content != null) ? o.content.length : 1
      }
-      yield * this.setState(state)
+      this.setState(state)
    }
    /*
      apply a delete set in order to get
      the state of the supplied ds
    */
-    * applyDeleteSet (decoder) {
+    applyDeleteSet (decoder) {
      var deletions = []

      let dsLength = decoder.readUint32()
@@ -606,7 +606,7 @@ export default function extendTransaction (Y) {
        }
        var pos = 0
        var d = dv[pos]
-        yield * this.ds.iterate(this, [user, 0], [user, Number.MAX_VALUE], function * (n) {
+        this.ds.iterate(this, [user, 0], [user, Number.MAX_VALUE], function (n) {
          // cases:
          // 1. d deletes something to the right of n
          //  => go to next n (break)
@@ -655,14 +655,14 @@ export default function extendTransaction (Y) {
      for (var i = 0; i < deletions.length; i++) {
        var del = deletions[i]
        // always try to delete..
-        yield * this.deleteOperation([del[0], del[1]], del[2])
+        this.deleteOperation([del[0], del[1]], del[2])
        if (del[3]) {
          // gc..
-          yield * this.markGarbageCollected([del[0], del[1]], del[2]) // always mark gc'd
+          this.markGarbageCollected([del[0], del[1]], del[2]) // always mark gc'd
          // remove operation..
          var counter = del[1] + del[2]
          while (counter >= del[1]) {
-            var o = yield * this.os.findWithUpperBound([del[0], counter - 1])
+            var o = this.os.findWithUpperBound([del[0], counter - 1])
            if (o == null) {
              break
            }
@@ -673,14 +673,14 @@ export default function extendTransaction (Y) {
            }
            if (o.id[1] + oLen > del[1] + del[2]) {
              // overlaps right
-              o = yield * this.getInsertionCleanEnd([del[0], del[1] + del[2] - 1])
+              o = this.getInsertionCleanEnd([del[0], del[1] + del[2] - 1])
            }
            if (o.id[1] < del[1]) {
              // overlaps left
-              o = yield * this.getInsertionCleanStart([del[0], del[1]])
+              o = this.getInsertionCleanStart([del[0], del[1]])
            }
            counter = o.id[1]
-            yield * this.garbageCollectOperation(o.id)
+            this.garbageCollectOperation(o.id)
          }
        }
        if (this.store.forwardAppliedOperations || this.store.y.persistence != null) {
@@ -695,16 +695,16 @@ export default function extendTransaction (Y) {
        }
      }
    }
-    * isGarbageCollected (id) {
-      var n = yield * this.ds.findWithUpperBound(id)
+    isGarbageCollected (id) {
+      var n = this.ds.findWithUpperBound(id)
      return n != null && n.id[0] === id[0] && id[1] < n.id[1] + n.len && n.gc
    }
    /*
      A DeleteSet (ds) describes all the deleted ops in the OS
    */
-    * writeDeleteSet (encoder) {
+    writeDeleteSet (encoder) {
      var ds = new Map()
-      yield * this.ds.iterate(this, null, null, function * (n) {
+      this.ds.iterate(this, null, null, function (n) {
        var user = n.id[0]
        var counter = n.id[1]
        var len = n.len
@@ -731,16 +731,16 @@ export default function extendTransaction (Y) {
        }
      }
    }
-    * isDeleted (id) {
-      var n = yield * this.ds.findWithUpperBound(id)
+    isDeleted (id) {
+      var n = this.ds.findWithUpperBound(id)
      return n != null && n.id[0] === id[0] && id[1] < n.id[1] + n.len
    }
-    * setOperation (op) {
-      yield * this.os.put(op)
+    setOperation (op) {
+      this.os.put(op)
      return op
    }
-    * addOperation (op) {
-      yield * this.os.put(op)
+    addOperation (op) {
+      this.os.put(op)
      // case op is created by this user, op is already broadcasted in applyCreatedOperations
      if (op.id[0] !== this.store.userId && typeof op.id[1] !== 'string') {
        if (this.store.forwardAppliedOperations) {
@@ -753,7 +753,7 @@ export default function extendTransaction (Y) {
      }
    }
    // if insertion, try to combine with left insertion (if both have content property)
-    * tryCombineWithLeft (op) {
+    tryCombineWithLeft (op) {
      if (
        op != null &&
        op.left != null &&
@@ -761,7 +761,7 @@ export default function extendTransaction (Y) {
        op.left[0] === op.id[0] &&
        Y.utils.compareIds(op.left, op.origin)
      ) {
-        var left = yield * this.getInsertion(op.left)
+        var left = this.getInsertion(op.left)
        if (left.content != null &&
            left.id[1] + left.content.length === op.id[1] &&
            left.originOf.length === 1 &&
@@ -776,13 +776,13 @@ export default function extendTransaction (Y) {
          }
          left.content = left.content.concat(op.content)
          left.right = op.right
-          yield * this.os.delete(op.id)
-          yield * this.setOperation(left)
+          this.os.delete(op.id)
+          this.setOperation(left)
        }
      }
    }
-    * getInsertion (id) {
-      var ins = yield * this.os.findWithUpperBound(id)
+    getInsertion (id) {
+      var ins = this.os.findWithUpperBound(id)
      if (ins == null) {
        return null
      } else {
@@ -794,14 +794,14 @@ export default function extendTransaction (Y) {
        }
      }
    }
-    * getInsertionCleanStartEnd (id) {
-      yield * this.getInsertionCleanStart(id)
-      return yield * this.getInsertionCleanEnd(id)
+    getInsertionCleanStartEnd (id) {
+      this.getInsertionCleanStart(id)
+      return this.getInsertionCleanEnd(id)
    }
    // Return an insertion such that id is the first element of content
    // This function manipulates an operation, if necessary
-    * getInsertionCleanStart (id) {
-      var ins = yield * this.getInsertion(id)
+    getInsertionCleanStart (id) {
+      var ins = this.getInsertion(id)
      if (ins != null) {
        if (ins.id[1] === id[1]) {
          return ins
@@ -815,8 +815,8 @@ export default function extendTransaction (Y) {
          left.right = ins.id
          ins.left = leftLid
          // debugger // check
-          yield * this.setOperation(left)
-          yield * this.setOperation(ins)
+          this.setOperation(left)
+          this.setOperation(ins)
          if (left.gc) {
            this.store.queueGarbageCollector(ins.id)
          }
@@ -828,8 +828,8 @@ export default function extendTransaction (Y) {
    }
    // Return an insertion such that id is the last element of content
    // This function manipulates an operation, if necessary
-    * getInsertionCleanEnd (id) {
-      var ins = yield * this.getInsertion(id)
+    getInsertionCleanEnd (id) {
+      var ins = this.getInsertion(id)
      if (ins != null) {
        if (ins.content == null || (ins.id[1] + ins.content.length - 1 === id[1])) {
          return ins
@@ -843,8 +843,8 @@ export default function extendTransaction (Y) {
          ins.right = right.id
          right.left = insLid
          // debugger // check
-          yield * this.setOperation(right)
-          yield * this.setOperation(ins)
+          this.setOperation(right)
+          this.setOperation(ins)
          if (ins.gc) {
            this.store.queueGarbageCollector(right.id)
          }
@@ -854,8 +854,8 @@ export default function extendTransaction (Y) {
        return null
      }
    }
-    * getOperation (id/* :any */)/* :Transaction<any> */ {
-      var o = yield * this.os.find(id)
+    getOperation (id/* :any */)/* :Transaction<any> */ {
+      var o = this.os.find(id)
      if (id[0] !== 0xFFFFFF || o != null) {
        return o
      } else { // type is string
@@ -863,9 +863,14 @@ export default function extendTransaction (Y) {
        var comp = id[1].split('_')
        if (comp.length > 1) {
          var struct = comp[0]
-          var op = Y.Struct[struct].create(id)
+          let type = Y[comp[1]]
+          let args = null
+          if (type != null) {
+            args = Y.utils.parseTypeDefinition(type, comp[3])
+          }
+          var op = Y.Struct[struct].create(id, args)
          op.type = comp[1]
-          yield * this.setOperation(op)
+          this.setOperation(op)
          return op
        } else {
          throw new Error(
@@ -875,18 +880,18 @@ export default function extendTransaction (Y) {
        }
      }
    }
-    * removeOperation (id) {
-      yield * this.os.delete(id)
+    removeOperation (id) {
+      this.os.delete(id)
    }
-    * setState (state) {
+    setState (state) {
      var val = {
        id: [state.user],
        clock: state.clock
      }
-      yield * this.ss.put(val)
+      this.ss.put(val)
    }
-    * getState (user) {
-      var n = yield * this.ss.find([user])
+    getState (user) {
+      var n = this.ss.find([user])
      var clock = n == null ? null : n.clock
      if (clock == null) {
        clock = 0
@@ -896,9 +901,9 @@ export default function extendTransaction (Y) {
        clock: clock
      }
    }
-    * getStateVector () {
+    getStateVector () {
      var stateVector = []
-      yield * this.ss.iterate(this, null, null, function * (n) {
+      this.ss.iterate(this, null, null, function (n) {
        stateVector.push({
          user: n.id[0],
          clock: n.clock
@@ -906,18 +911,18 @@ export default function extendTransaction (Y) {
      })
      return stateVector
    }
-    * getStateSet () {
+    getStateSet () {
      var ss = {}
-      yield * this.ss.iterate(this, null, null, function * (n) {
+      this.ss.iterate(this, null, null, function (n) {
        ss[n.id[0]] = n.clock
      })
      return ss
    }
-    * writeStateSet (encoder) {
+    writeStateSet (encoder) {
      let lenPosition = encoder.pos
      let len = 0
      encoder.writeUint32(0)
-      yield * this.ss.iterate(this, null, null, function * (n) {
+      this.ss.iterate(this, null, null, function (n) {
        encoder.writeVarUint(n.id[0])
        encoder.writeVarUint(n.clock)
        len++
@@ -971,14 +976,14 @@ export default function extendTransaction (Y) {
        3. Found o = op.origin -> set op.left = op.origin, and send it to the user. start again from 1. (set op = o)
        4. Found some o -> set o.right = op, o.left = o.origin, send it to the user, continue
    */
-    * getOperations (startSS) {
+    getOperations (startSS) {
      // TODO: use bounds here!
      if (startSS == null) {
        startSS = new Map()
      }
      var send = []

-      var endSV = yield * this.getStateVector()
+      var endSV = this.getStateVector()
      for (let endState of endSV) {
        let user = endState.user
        if (user === 0xFFFFFF) {
@@ -988,7 +993,7 @@ export default function extendTransaction (Y) {
        if (startPos > 0) {
          // There is a change that [user, startPos] is in a composed Insertion (with a smaller counter)
          // find out if that is the case
-          let firstMissing = yield * this.getInsertion([user, startPos])
+          let firstMissing = this.getInsertion([user, startPos])
          if (firstMissing != null) {
            // update startPos
            startPos = firstMissing.id[1]
@@ -1002,7 +1007,7 @@ export default function extendTransaction (Y) {
        if (user === 0xFFFFFF) {
          continue
        }
-        yield * this.os.iterate(this, [user, startPos], [user, Number.MAX_VALUE], function * (op) {
+        this.os.iterate(this, [user, startPos], [user, Number.MAX_VALUE], function (op) {
          op = Y.Struct[op.struct].encode(op)
          if (op.struct !== 'Insert') {
            send.push(op)
@@ -1033,7 +1038,7 @@ export default function extendTransaction (Y) {
                */
                break
              }
-              o = yield * this.getInsertion(o.left)
+              o = this.getInsertion(o.left)
              // we set another o, check if we can reduce $missingOrigins
              while (missingOrigins.length > 0 && Y.utils.matchesId(o, missingOrigins[missingOrigins.length - 1].origin)) {
                missingOrigins.pop()
@@ -1071,7 +1076,7 @@ export default function extendTransaction (Y) {
      return send.reverse()
    }

-    * writeOperations (encoder, decoder) {
+    writeOperations (encoder, decoder) {
      let ss = new Map()
      let ssLength = decoder.readUint32()
      for (let i = 0; i < ssLength; i++) {
@@ -1079,7 +1084,7 @@ export default function extendTransaction (Y) {
        let clock = decoder.readVarUint()
        ss.set(user, clock)
      }
-      let ops = yield * this.getOperations(ss)
+      let ops = this.getOperations(ss)
      encoder.writeUint32(ops.length)
      for (let i = 0; i < ops.length; i++) {
        let op = ops[i]
@@ -1087,17 +1092,17 @@ export default function extendTransaction (Y) {
      }
    }

-    * toBinary () {
+    toBinary () {
      let encoder = new BinaryEncoder()
-      yield * this.writeOperationsUntransformed(encoder)
-      yield * this.writeDeleteSet(encoder)
+      this.writeOperationsUntransformed(encoder)
+      this.writeDeleteSet(encoder)
      return encoder.createBuffer()
    }

-    * fromBinary (buffer) {
+    fromBinary (buffer) {
      let decoder = new BinaryDecoder(buffer)
-      yield * this.applyOperationsUntransformed(decoder)
-      yield * this.applyDeleteSet(decoder)
+      this.applyOperationsUntransformed(decoder)
+      this.applyDeleteSet(decoder)
    }

    /*
@@ -1105,43 +1110,43 @@ export default function extendTransaction (Y) {
     * You can apply these operations using .applyOperationsUntransformed(ops)
     *
     */
-    * writeOperationsUntransformed (encoder) {
+    writeOperationsUntransformed (encoder) {
      let lenPosition = encoder.pos
      let len = 0
      encoder.writeUint32(0) // placeholder
-      yield * this.os.iterate(this, null, null, function * (op) {
+      this.os.iterate(this, null, null, function (op) {
        if (op.id[0] !== 0xFFFFFF) {
          len++
          Y.Struct[op.struct].binaryEncode(encoder, Y.Struct[op.struct].encode(op))
        }
      })
      encoder.setUint32(lenPosition, len)
-      yield * this.writeStateSet(encoder)
+      this.writeStateSet(encoder)
    }
-    * applyOperationsUntransformed (decoder) {
+    applyOperationsUntransformed (decoder) {
      let len = decoder.readUint32()
      for (let i = 0; i < len; i++) {
        let op = Y.Struct.binaryDecodeOperation(decoder)
-        yield * this.os.put(op)
+        this.os.put(op)
      }
-      yield * this.os.iterate(this, null, null, function * (op) {
+      this.os.iterate(this, null, null, function (op) {
        if (op.parent != null) {
          if (op.struct === 'Insert') {
            // update parents .map/start/end properties
            if (op.parentSub != null && op.left == null) {
              // op is child of Map
-              let parent = yield * this.getOperation(op.parent)
+              let parent = this.getOperation(op.parent)
              parent.map[op.parentSub] = op.id
-              yield * this.setOperation(parent)
+              this.setOperation(parent)
            } else if (op.right == null || op.left == null) {
-              let parent = yield * this.getOperation(op.parent)
+              let parent = this.getOperation(op.parent)
              if (op.right == null) {
                parent.end = Y.utils.getLastId(op)
              }
              if (op.left == null) {
                parent.start = op.id
              }
-              yield * this.setOperation(parent)
+              this.setOperation(parent)
            }
          }
        }
@@ -1150,14 +1155,14 @@ export default function extendTransaction (Y) {
      for (let i = 0; i < stateSetLength; i++) {
        let user = decoder.readVarUint()
        let clock = decoder.readVarUint()
-        yield * this.ss.put({
+        this.ss.put({
          id: [user],
          clock: clock
        })
      }
    }
    /* this is what we used before.. use this as a reference..
-    * makeOperationReady (startSS, op) {
+    makeOperationReady (startSS, op) {
      op = Y.Struct[op.struct].encode(op)
      op = Y.utils.copyObject(op) -- use copyoperation instead now!
      var o = op
@@ -1167,7 +1172,7 @@ export default function extendTransaction (Y) {
      // or the o that has no origin to the right of op
      // (this is why we use the ids array)
      while (o.right != null) {
-        var right = yield * this.getOperation(o.right)
+        var right = this.getOperation(o.right)
        if (o.right[1] < (startSS[o.right[0]] || 0) || !ids.some(function (id) {
          return Y.utils.compareIds(id, right.origin)
        })) {
@@ -1181,10 +1186,10 @@ export default function extendTransaction (Y) {
      return op
    }
    */
-    * flush () {
-      yield * this.os.flush()
-      yield * this.ss.flush()
-      yield * this.ds.flush()
+    flush () {
+      this.os.flush()
+      this.ss.flush()
+      this.ds.flush()
    }
  }
  Y.Transaction = TransactionInterface
--- a/src/Utils.js
+++ b/src/Utils.js
@@ -49,6 +49,51 @@ export default function Utils (Y) {
    }
  }

+  Y.utils.getRelativePosition = function (type, offset) {
+    if (type == null) {
+      return null
+    } else {
+      if (type._content.length <= offset) {
+        return ['endof', type._model[0], type._model[1]]
+      } else {
+        return type._content[offset].id
+      }
+    }
+  }
+
+  Y.utils.fromRelativePosition = function (y, id) {
+    var offset = 0
+    var op
+    if (id[0] === 'endof') {
+      id = y.db.os.find(id.slice(1)).end
+      op = y.db.os.findNodeWithUpperBound(id).val
+      if (!op.deleted) {
+        offset = op.content != null ? op.content.length : 1
+      }
+    } else {
+      op = y.db.os.findNodeWithUpperBound(id).val
+      if (!op.deleted) {
+        offset = id[1] - op.id[1]
+      }
+    }
+
+    var type = y.db.getType(op.parent)
+    if (type == null || y.db.os.find(op.parent).deleted) {
+      return null
+    }
+
+    while (op.left != null) {
+      op = y.db.os.findNodeWithUpperBound(op.left).val
+      if (!op.deleted) {
+        offset += op.content != null ? op.content.length : 1
+      }
+    }
+    return {
+      type: type,
+      offset: offset
+    }
+  }
+
  class NamedEventHandler {
    constructor () {
      this._eventListener = {}
@@ -67,7 +112,11 @@ export default function Utils (Y) {
      this._eventListener[name] = listener.filter(e => e !== f)
    }
    emit (name, value) {
-      (this._eventListener[name] || []).forEach(l => l(value))
+      let listener = this._eventListener[name] || []
+      if (name === 'error' && listener.length === 0) {
+        console.error(value)
+      }
+      listener.forEach(l => l(value))
    }
    destroy () {
      this._eventListener = null
@@ -315,7 +364,7 @@ export default function Utils (Y) {
      this.awaiting++
      ops.map(Y.utils.copyOperation).forEach(this.onevent)
    }
-    * awaitOps (transaction, f, args) {
+    awaitOps (transaction, f, args) {
      function notSoSmartSort (array) {
        // this function sorts insertions in a executable order
        var result = []
@@ -339,7 +388,7 @@ export default function Utils (Y) {
      }
      var before = this.waiting.length
      // somehow create new operations
-      yield * f.apply(transaction, args)
+      f.apply(transaction, args)
      // remove all appended ops / awaited ops
      this.waiting.splice(before)
      if (this.awaiting > 0) this.awaiting--
@@ -349,7 +398,7 @@ export default function Utils (Y) {
        for (let i = 0; i < this.waiting.length; i++) {
          var o = this.waiting[i]
          if (o.struct === 'Insert') {
-            var _o = yield * transaction.getInsertion(o.id)
+            var _o = transaction.getInsertion(o.id)
            if (_o.parentSub != null && _o.left != null) {
              // if o is an insertion of a map struc (parentSub is defined), then it shouldn't be necessary to compute left
              this.waiting.splice(i, 1)
@@ -361,10 +410,10 @@ export default function Utils (Y) {
              o.left = null
            } else {
              // find next undeleted op
-              var left = yield * transaction.getInsertion(_o.left)
+              var left = transaction.getInsertion(_o.left)
              while (left.deleted != null) {
                if (left.left != null) {
-                  left = yield * transaction.getInsertion(left.left)
+                  left = transaction.getInsertion(left.left)
                } else {
                  left = null
                  break
@@ -690,7 +739,7 @@ export default function Utils (Y) {
        this.writeBuffer = createEmptyOpsArray(5)
        this.readBuffer = createEmptyOpsArray(10)
      }
-      * find (id, noSuperCall) {
+      find (id, noSuperCall) {
        var i, r
        for (i = this.readBuffer.length - 1; i >= 0; i--) {
          r = this.readBuffer[i]
@@ -716,7 +765,7 @@ export default function Utils (Y) {
        if (i < 0 && noSuperCall === undefined) {
          // did not reach break in last loop
          // read id and put it to the end of readBuffer
-          o = yield * super.find(id)
+          o = super.find(id)
        }
        if (o != null) {
          for (i = 0; i < this.readBuffer.length - 1; i++) {
@@ -726,7 +775,7 @@ export default function Utils (Y) {
        }
        return o
      }
-      * put (o) {
+      put (o) {
        var id = o.id
        var i, r // helper variables
        for (i = this.writeBuffer.length - 1; i >= 0; i--) {
@@ -746,7 +795,7 @@ export default function Utils (Y) {
          // write writeBuffer[0]
          var write = this.writeBuffer[0]
          if (write.id[0] !== null) {
-            yield * super.put(write)
+            super.put(write)
          }
          // put o to the end of writeBuffer
          for (i = 0; i < this.writeBuffer.length - 1; i++) {
@@ -766,7 +815,7 @@ export default function Utils (Y) {
        }
        this.readBuffer[this.readBuffer.length - 1] = o
      }
-      * delete (id) {
+      delete (id) {
        var i, r
        for (i = 0; i < this.readBuffer.length; i++) {
          r = this.readBuffer[i]
@@ -776,44 +825,44 @@ export default function Utils (Y) {
            }
          }
        }
-        yield * this.flush()
-        yield * super.delete(id)
+        this.flush()
+        super.delete(id)
      }
-      * findWithLowerBound (id) {
-        var o = yield * this.find(id, true)
+      findWithLowerBound (id) {
+        var o = this.find(id, true)
        if (o != null) {
          return o
        } else {
-          yield * this.flush()
-          return yield * super.findWithLowerBound.apply(this, arguments)
+          this.flush()
+          return super.findWithLowerBound.apply(this, arguments)
        }
      }
-      * findWithUpperBound (id) {
-        var o = yield * this.find(id, true)
+      findWithUpperBound (id) {
+        var o = this.find(id, true)
        if (o != null) {
          return o
        } else {
-          yield * this.flush()
-          return yield * super.findWithUpperBound.apply(this, arguments)
+          this.flush()
+          return super.findWithUpperBound.apply(this, arguments)
        }
      }
-      * findNext () {
-        yield * this.flush()
-        return yield * super.findNext.apply(this, arguments)
+      findNext () {
+        this.flush()
+        return super.findNext.apply(this, arguments)
      }
-      * findPrev () {
-        yield * this.flush()
-        return yield * super.findPrev.apply(this, arguments)
+      findPrev () {
+        this.flush()
+        return super.findPrev.apply(this, arguments)
      }
-      * iterate () {
-        yield * this.flush()
-        yield * super.iterate.apply(this, arguments)
+      iterate () {
+        this.flush()
+        super.iterate.apply(this, arguments)
      }
-      * flush () {
+      flush () {
        for (var i = 0; i < this.writeBuffer.length; i++) {
          var write = this.writeBuffer[i]
          if (write.id[0] !== null) {
-            yield * super.put(write)
+            super.put(write)
            this.writeBuffer[i] = {
              id: [null, null]
            }
@@ -840,4 +889,47 @@ export default function Utils (Y) {
    }
  }
  Y.utils.generateUserId = generateUserId
+
+  Y.utils.parseTypeDefinition = function parseTypeDefinition (type, typeArgs) {
+    var args = []
+    try {
+      args = JSON.parse('[' + typeArgs + ']')
+    } catch (e) {
+      throw new Error('Was not able to parse type definition!')
+    }
+    if (type.typeDefinition.parseArguments != null) {
+      args = type.typeDefinition.parseArguments(args[0])[1]
+    }
+    return args
+  }
+
+  Y.utils.writeObjectToYMap = function writeObjectToYMap (object, type) {
+    for (var key in object) {
+      var val = object[key]
+      if (Array.isArray(val)) {
+        type.set(key, Y.Array)
+        Y.utils.writeArrayToYArray(val, type.get(key))
+      } else if (typeof val === 'object') {
+        type.set(key, Y.Map)
+        Y.utils.writeObjectToYMap(val, type.get(key))
+      } else {
+        type.set(key, val)
+      }
+    }
+  }
+
+  Y.utils.writeArrayToYArray = function writeArrayToYArray (array, type) {
+    for (var i = array.length - 1; i >= 0; i--) {
+      var val = array[i]
+      if (Array.isArray(val)) {
+        type.insert(0, [Y.Array])
+        Y.utils.writeArrayToYArray(val, type.get(0))
+      } else if (typeof val === 'object') {
+        type.insert(0, [Y.Map])
+        Y.utils.writeObjectToYMap(val, type.get(0))
+      } else {
+        type.insert(0, [val])
+      }
+    }
+  }
 }
--- a/src/y-memory.js
+++ b/src/y-memory.js
@@ -0,0 +1,67 @@
+import extendRBTree from './RedBlackTree'
+
+export default function extend (Y) {
+  extendRBTree(Y)
+
+  class Transaction extends Y.Transaction {
+    constructor (store) {
+      super(store)
+      this.store = store
+      this.ss = store.ss
+      this.os = store.os
+      this.ds = store.ds
+    }
+  }
+  var Store = Y.utils.RBTree
+  var BufferedStore = Y.utils.createSmallLookupBuffer(Store)
+
+  class Database extends Y.AbstractDatabase {
+    constructor (y, opts) {
+      super(y, opts)
+      this.os = new BufferedStore()
+      this.ds = new Store()
+      this.ss = new BufferedStore()
+    }
+    logTable () {
+      var self = this
+      self.requestTransaction(function () {
+        console.log('User: ', this.store.y.connector.userId, "==============================") // eslint-disable-line
+        console.log("State Set (SS):", this.getStateSet()) // eslint-disable-line
+        console.log("Operation Store (OS):") // eslint-disable-line
+        this.os.logTable() // eslint-disable-line
+        console.log("Deletion Store (DS):") //eslint-disable-line
+        this.ds.logTable() // eslint-disable-line
+        if (this.store.gc1.length > 0 || this.store.gc2.length > 0) {
+          console.warn('GC1|2 not empty!', this.store.gc1, this.store.gc2)
+        }
+        if (JSON.stringify(this.store.listenersById) !== '{}') {
+          console.warn('listenersById not empty!')
+        }
+        if (JSON.stringify(this.store.listenersByIdExecuteNow) !== '[]') {
+          console.warn('listenersByIdExecuteNow not empty!')
+        }
+        if (this.store.transactionInProgress) {
+          console.warn('Transaction still in progress!')
+        }
+      }, true)
+    }
+    transact (makeGen) {
+      const t = new Transaction(this)
+      try {
+        while (makeGen != null) {
+          makeGen.call(t)
+          makeGen = this.getNextRequest()
+        }
+      } catch (e) {
+        this.y.emit('error', e)
+      }
+    }
+    destroy () {
+      super.destroy()
+      delete this.os
+      delete this.ss
+      delete this.ds
+    }
+  }
+  Y.memory = Database
+}
--- a/src/y.js
+++ b/src/y.js
@@ -4,6 +4,7 @@ import extendDatabase from './Database.js'
 import extendTransaction from './Transaction.js'
 import extendStruct from './Struct.js'
 import extendUtils from './Utils.js'
+import extendMemory from './y-memory.js'
 import debug from 'debug'
 import { formatYjsMessage, formatYjsMessageType } from './MessageHandler.js'

@@ -13,6 +14,7 @@ extendDatabase(Y)
 extendTransaction(Y)
 extendStruct(Y)
 extendUtils(Y)
+extendMemory(Y)

 Y.debug = debug
 debug.formatters.Y = formatYjsMessage
@@ -139,10 +141,23 @@ export default function Y (opts/* :YOptions */) /* :Promise<YConfig> */ {
      opts.share = Y.utils.copyObject(opts.share)
      Y.requestModules(modules).then(function () {
        var yconfig = new YConfig(opts)
+        let resolved = false
+        if (opts.timeout != null && opts.timeout >= 0) {
+          setTimeout(function () {
+            if (!resolved) {
+              reject(new Error('Yjs init timeout'))
+              yconfig.destroy()
+            }
+          }, opts.timeout)
+        }
+        if (yconfig.persistence != null) {
+          yconfig.persistence.retrieveContent()
+        }
        yconfig.db.whenUserIdSet(function () {
          yconfig.init(function () {
+            resolved = true
            resolve(yconfig)
-          })
+          }, reject)
        })
      }).catch(reject)
    }
@@ -172,38 +187,24 @@ class YConfig extends Y.utils.NamedEventHandler {
    var opts = this.options
    var share = {}
    this.share = share
-    this.db.requestTransaction(function * requestTransaction () {
+    this.db.requestTransaction(function requestTransaction () {
      // create shared object
      for (var propertyname in opts.share) {
        var typeConstructor = opts.share[propertyname].split('(')
+        let typeArgs = ''
+        if (typeConstructor.length === 2) {
+          typeArgs = typeConstructor[1].split(')')[0] || ''
+        }
        var typeName = typeConstructor.splice(0, 1)
        var type = Y[typeName]
        var typedef = type.typeDefinition
-        var id = [0xFFFFFF, typedef.struct + '_' + typeName + '_' + propertyname + '_' + typeConstructor]
-        var args = []
-        if (typeConstructor.length === 1) {
-          try {
-            args = JSON.parse('[' + typeConstructor[0].split(')')[0] + ']')
-          } catch (e) {
-            throw new Error('Was not able to parse type definition! (share.' + propertyname + ')')
-          }
-          if (type.typeDefinition.parseArguments == null) {
-            throw new Error(typeName + ' does not expect arguments!')
-          } else {
-            args = typedef.parseArguments(args[0])[1]
-          }
-        }
-        share[propertyname] = yield * this.store.initType.call(this, id, args)
+        var id = [0xFFFFFF, typedef.struct + '_' + typeName + '_' + propertyname + '_' + typeArgs]
+        let args = Y.utils.parseTypeDefinition(type, typeArgs)
+        share[propertyname] = this.store.initType.call(this, id, args)
      }
    })
-    if (this.persistence != null) {
-      this.persistence.retrieveContent()
-        .then(() => this.db.whenTransactionsFinished())
-        .then(callback)
-    } else {
-      this.db.whenTransactionsFinished()
-        .then(callback)
-    }
+    this.db.whenTransactionsFinished()
+      .then(callback)
  }
  isConnected () {
    return this.connector.isSynced
@@ -248,8 +249,8 @@ class YConfig extends Y.utils.NamedEventHandler {
    return this.db.whenTransactionsFinished().then(function () {
      self.db.destroyTypes()
      // make sure to wait for all transactions before destroying the db
-      self.db.requestTransaction(function * () {
-        yield * self.db.destroy()
+      self.db.requestTransaction(function () {
+        self.db.destroy()
      })
      return self.db.whenTransactionsFinished()
    })
--- a/test/encode-decode.js
+++ b/test/encode-decode.js
@@ -158,34 +158,12 @@ const writeList = Y.Struct.List.binaryEncode
 const readList = Y.Struct.List.binaryDecode

 test('encode/decode List operations', async function binList (t) {
-  testEncoding(t, writeList, readList, {
-    struct: 'List',
-    id: [100, 33],
-    type: 'Array'
-  })
-
-  t.log('info is an object')
  testEncoding(t, writeList, readList, {
    struct: 'List',
    id: [100, 33],
    type: 'Array',
-    info: { prop: 'yay' }
-  })
-
-  t.log('info is a string')
-  testEncoding(t, writeList, readList, {
-    struct: 'List',
-    id: [100, 33],
-    type: 'Array',
-    info: 'hi'
-  })
-
-  t.log('info is a number')
-  testEncoding(t, writeList, readList, {
-    struct: 'List',
-    id: [100, 33],
-    type: 'Array',
-    info: 400
+    start: null,
+    end: null
  })
 })

@@ -199,31 +177,4 @@ test('encode/decode Map operations', async function binMap (t) {
    type: 'Map',
    map: {}
  })
-
-  t.log('info is an object')
-  testEncoding(t, writeMap, readMap, {
-    struct: 'Map',
-    id: [100, 33],
-    type: 'Map',
-    info: { prop: 'yay' },
-    map: {}
-  })
-
-  t.log('info is a string')
-  testEncoding(t, writeMap, readMap, {
-    struct: 'Map',
-    id: [100, 33],
-    type: 'Map',
-    map: {},
-    info: 'hi'
-  })
-
-  t.log('info is a number')
-  testEncoding(t, writeMap, readMap, {
-    struct: 'Map',
-    id: [100, 33],
-    type: 'Map',
-    map: {},
-    info: 400
-  })
 })
--- a/test/red-black-tree.js
+++ b/test/red-black-tree.js
@@ -0,0 +1,217 @@
+import Y from '../src/y.js'
+import Chance from 'chance'
+import { test, proxyConsole } from 'cutest'
+
+proxyConsole()
+
+var numberOfRBTreeTests = 10000
+
+function checkRedNodesDoNotHaveBlackChildren (t, tree) {
+  let correct = true
+  function traverse (n) {
+    if (n == null) {
+      return
+    }
+    if (n.isRed()) {
+      if (n.left != null) {
+        correct = correct && !n.left.isRed()
+      }
+      if (n.right != null) {
+        correct = correct && !n.right.isRed()
+      }
+    }
+    traverse(n.left)
+    traverse(n.right)
+  }
+  traverse(tree.root)
+  t.assert(correct, 'Red nodes do not have black children')
+}
+
+function checkBlackHeightOfSubTreesAreEqual (t, tree) {
+  let correct = true
+  function traverse (n) {
+    if (n == null) {
+      return 0
+    }
+    var sub1 = traverse(n.left)
+    var sub2 = traverse(n.right)
+    if (sub1 !== sub2) {
+      correct = false
+    }
+    if (n.isRed()) {
+      return sub1
+    } else {
+      return sub1 + 1
+    }
+  }
+  traverse(tree.root)
+  t.assert(correct, 'Black-height of sub-trees are equal')
+}
+
+function checkRootNodeIsBlack (t, tree) {
+  t.assert(tree.root == null || tree.root.isBlack(), 'root node is black')
+}
+
+test('RedBlack Tree', async function redBlackTree (t) {
+  let memory = new Y.memory(null, { // eslint-disable-line
+    name: 'Memory',
+    gcTimeout: -1
+  })
+  let tree = memory.os
+  memory.requestTransaction(function () {
+    tree.put({id: [8433]})
+    tree.put({id: [12844]})
+    tree.put({id: [1795]})
+    tree.put({id: [30302]})
+    tree.put({id: [64287]})
+    tree.delete([8433])
+    tree.put({id: [28996]})
+    tree.delete([64287])
+    tree.put({id: [22721]})
+  })
+  await memory.whenTransactionsFinished()
+  checkRootNodeIsBlack(t, tree)
+  checkBlackHeightOfSubTreesAreEqual(t, tree)
+  checkRedNodesDoNotHaveBlackChildren(t, tree)
+})
+
+test(`random tests (${numberOfRBTreeTests})`, async function random (t) {
+  let chance = new Chance(t.getSeed() * 1000000000)
+  let memory = new Y.memory(null, { // eslint-disable-line
+    name: 'Memory',
+    gcTimeout: -1
+  })
+  let tree = memory.os
+  let elements = []
+  memory.requestTransaction(function () {
+    for (var i = 0; i < numberOfRBTreeTests; i++) {
+      if (chance.bool({likelihood: 80})) {
+        // 80% chance to insert an element
+        let obj = [chance.integer({min: 0, max: numberOfRBTreeTests})]
+        let nodeExists = tree.find(obj)
+        if (!nodeExists) {
+          if (elements.some(e => e[0] === obj[0])) {
+            t.assert(false, 'tree and elements contain different results')
+          }
+          elements.push(obj)
+          tree.put({id: obj})
+        }
+      } else if (elements.length > 0) {
+        // ~20% chance to delete an element
+        var elem = chance.pickone(elements)
+        elements = elements.filter(function (e) {
+          return !Y.utils.compareIds(e, elem)
+        })
+        tree.delete(elem)
+      }
+    }
+  })
+  await memory.whenTransactionsFinished()
+  checkRootNodeIsBlack(t, tree)
+  checkBlackHeightOfSubTreesAreEqual(t, tree)
+  checkRedNodesDoNotHaveBlackChildren(t, tree)
+  memory.requestTransaction(function () {
+    let allNodesExist = true
+    for (let id of elements) {
+      let node = tree.find(id)
+      if (!Y.utils.compareIds(node.id, id)) {
+        allNodesExist = false
+      }
+    }
+    t.assert(allNodesExist, 'All inserted nodes exist')
+  })
+  memory.requestTransaction(function () {
+    let findAllNodesWithLowerBoundSerach = true
+    for (let id of elements) {
+      let node = tree.findWithLowerBound(id)
+      if (!Y.utils.compareIds(node.id, id)) {
+        findAllNodesWithLowerBoundSerach = false
+      }
+    }
+    t.assert(
+      findAllNodesWithLowerBoundSerach,
+      'Find every object with lower bound search'
+    )
+  })
+
+  memory.requestTransaction(function () {
+    let lowerBound = chance.pickone(elements)
+    let expectedResults = elements.filter((e, pos) =>
+      (Y.utils.smaller(lowerBound, e) || Y.utils.compareIds(e, lowerBound)) &&
+      elements.indexOf(e) === pos
+    ).length
+    let actualResults = 0
+    tree.iterate(this, lowerBound, null, function (val) {
+      if (val == null) {
+        t.assert(false, 'val is undefined!')
+      }
+      actualResults++
+    })
+    t.assert(
+      expectedResults === actualResults,
+      'Iterating over a tree with lower bound yields the right amount of results'
+    )
+  })
+
+  memory.requestTransaction(function () {
+    let expectedResults = elements.filter((e, pos) =>
+      elements.indexOf(e) === pos
+    ).length
+    let actualResults = 0
+    tree.iterate(this, null, null, function (val) {
+      if (val == null) {
+        t.assert(false, 'val is undefined!')
+      }
+      actualResults++
+    })
+    t.assert(
+      expectedResults === actualResults,
+      'iterating over a tree without bounds yields the right amount of results'
+    )
+  })
+
+  memory.requestTransaction(function () {
+    let upperBound = chance.pickone(elements)
+    let expectedResults = elements.filter((e, pos) =>
+      (Y.utils.smaller(e, upperBound) || Y.utils.compareIds(e, upperBound)) &&
+      elements.indexOf(e) === pos
+    ).length
+    let actualResults = 0
+    tree.iterate(this, null, upperBound, function (val) {
+      if (val == null) {
+        t.assert(false, 'val is undefined!')
+      }
+      actualResults++
+    })
+    t.assert(
+      expectedResults === actualResults,
+      'iterating over a tree with upper bound yields the right amount of results'
+    )
+  })
+
+  memory.requestTransaction(function () {
+    let upperBound = chance.pickone(elements)
+    let lowerBound = chance.pickone(elements)
+    if (Y.utils.smaller(upperBound, lowerBound)) {
+      [lowerBound, upperBound] = [upperBound, lowerBound]
+    }
+    let expectedResults = elements.filter((e, pos) =>
+      (Y.utils.smaller(lowerBound, e) || Y.utils.compareIds(e, lowerBound)) &&
+      (Y.utils.smaller(e, upperBound) || Y.utils.compareIds(e, upperBound)) &&
+      elements.indexOf(e) === pos
+    ).length
+    let actualResults = 0
+    tree.iterate(this, lowerBound, upperBound, function (val) {
+      if (val == null) {
+        t.assert(false, 'val is undefined!')
+      }
+      actualResults++
+    })
+    t.assert(
+      expectedResults === actualResults,
+      'iterating over a tree with upper bound yields the right amount of results'
+    )
+  })
+
+  await memory.whenTransactionsFinished()
+})
--- a/test/y-xml.tests.js
+++ b/test/y-xml.tests.js
@@ -0,0 +1,352 @@
+import { wait, initArrays, compareUsers, Y, flushAll, applyRandomTests } from '../../yjs/tests-lib/helper.js'
+import { test } from 'cutest'
+
+test('set property', async function xml0 (t) {
+  var { users, xml0, xml1 } = await initArrays(t, { users: 2 })
+  xml0.setAttribute('height', 10)
+  t.assert(xml0.getAttribute('height') === 10, 'Simple set+get works')
+  await flushAll(t, users)
+  t.assert(xml1.getAttribute('height') === 10, 'Simple set+get works (remote)')
+  await compareUsers(t, users)
+})
+
+test('events', async function xml1 (t) {
+  var { users, xml0, xml1 } = await initArrays(t, { users: 2 })
+  var event
+  var remoteEvent
+  let expectedEvent
+  xml0.observe(function (e) {
+    delete e._content
+    delete e.nodes
+    delete e.values
+    event = e
+  })
+  xml1.observe(function (e) {
+    delete e._content
+    delete e.nodes
+    delete e.values
+    remoteEvent = e
+  })
+  xml0.setAttribute('key', 'value')
+  expectedEvent = {
+    type: 'attributeChanged',
+    value: 'value',
+    name: 'key'
+  }
+  t.compare(event, expectedEvent, 'attribute changed event')
+  await flushAll(t, users)
+  t.compare(remoteEvent, expectedEvent, 'attribute changed event (remote)')
+  // check attributeRemoved
+  xml0.removeAttribute('key')
+  expectedEvent = {
+    type: 'attributeRemoved',
+    name: 'key'
+  }
+  t.compare(event, expectedEvent, 'attribute deleted event')
+  await flushAll(t, users)
+  t.compare(remoteEvent, expectedEvent, 'attribute deleted event (remote)')
+  // test childInserted event
+  expectedEvent = {
+    type: 'childInserted',
+    index: 0
+  }
+  xml0.insert(0, [Y.XmlText('some text')])
+  t.compare(event, expectedEvent, 'child inserted event')
+  await flushAll(t, users)
+  t.compare(remoteEvent, expectedEvent, 'child inserted event (remote)')
+  // test childRemoved
+  xml0.delete(0)
+  expectedEvent = {
+    type: 'childRemoved',
+    index: 0
+  }
+  t.compare(event, expectedEvent, 'child deleted event')
+  await flushAll(t, users)
+  t.compare(remoteEvent, expectedEvent, 'child deleted event (remote)')
+  await compareUsers(t, users)
+})
+
+test('attribute modifications (y -> dom)', async function xml2 (t) {
+  var { users, xml0 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  xml0.setAttribute('height', '100px')
+  await wait()
+  t.assert(dom0.getAttribute('height') === '100px', 'setAttribute')
+  xml0.removeAttribute('height')
+  await wait()
+  t.assert(dom0.getAttribute('height') == null, 'removeAttribute')
+  xml0.setAttribute('class', 'stuffy stuff')
+  await wait()
+  t.assert(dom0.getAttribute('class') === 'stuffy stuff', 'set class attribute')
+  await compareUsers(t, users)
+})
+
+test('attribute modifications (dom -> y)', async function xml3 (t) {
+  var { users, xml0 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  dom0.setAttribute('height', '100px')
+  await wait()
+  t.assert(xml0.getAttribute('height') === '100px', 'setAttribute')
+  dom0.removeAttribute('height')
+  await wait()
+  t.assert(xml0.getAttribute('height') == null, 'removeAttribute')
+  dom0.setAttribute('class', 'stuffy stuff')
+  await wait()
+  t.assert(xml0.getAttribute('class') === 'stuffy stuff', 'set class attribute')
+  await compareUsers(t, users)
+})
+
+test('element insert (dom -> y)', async function xml4 (t) {
+  var { users, xml0 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  dom0.insertBefore(document.createTextNode('some text'), null)
+  dom0.insertBefore(document.createElement('p'), null)
+  await wait()
+  t.assert(xml0.get(0).toString() === 'some text', 'Retrieve Text Node')
+  t.assert(xml0.get(1).nodeName === 'P', 'Retrieve Element node')
+  await compareUsers(t, users)
+})
+
+test('element insert (y -> dom)', async function xml5 (t) {
+  var { users, xml0 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  xml0.insert(0, [Y.XmlText('some text')])
+  xml0.insert(1, [Y.XmlElement('p')])
+  t.assert(dom0.childNodes[0].textContent === 'some text', 'Retrieve Text node')
+  t.assert(dom0.childNodes[1].nodeName === 'P', 'Retrieve Element node')
+  await compareUsers(t, users)
+})
+
+test('y on insert, then delete (dom -> y)', async function xml6 (t) {
+  var { users, xml0 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  dom0.insertBefore(document.createElement('p'), null)
+  await wait()
+  t.assert(xml0.length === 1, 'one node present')
+  dom0.childNodes[0].remove()
+  await wait()
+  t.assert(xml0.length === 0, 'no node present after delete')
+  await compareUsers(t, users)
+})
+
+test('y on insert, then delete (y -> dom)', async function xml7 (t) {
+  var { users, xml0 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  xml0.insert(0, [Y.XmlElement('p')])
+  t.assert(dom0.childNodes[0].nodeName === 'P', 'Get inserted element from dom')
+  xml0.delete(0, 1)
+  t.assert(dom0.childNodes.length === 0, '#childNodes is empty after delete')
+  await compareUsers(t, users)
+})
+
+test('delete consecutive (1) (Text)', async function xml8 (t) {
+  var { users, xml0 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  xml0.insert(0, ['1', '2', '3'].map(Y.XmlText))
+  await wait()
+  xml0.delete(1, 2)
+  await wait()
+  t.assert(xml0.length === 1, 'check length (y)')
+  t.assert(dom0.childNodes.length === 1, 'check length (dom)')
+  t.assert(dom0.childNodes[0].textContent === '1', 'check content')
+  await compareUsers(t, users)
+})
+
+test('delete consecutive (2) (Text)', async function xml9 (t) {
+  var { users, xml0 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  xml0.insert(0, ['1', '2', '3'].map(Y.XmlText))
+  await wait()
+  xml0.delete(0, 1)
+  xml0.delete(1, 1)
+  await wait()
+  t.assert(xml0.length === 1, 'check length (y)')
+  t.assert(dom0.childNodes.length === 1, 'check length (dom)')
+  t.assert(dom0.childNodes[0].textContent === '2', 'check content')
+  await compareUsers(t, users)
+})
+
+test('delete consecutive (1) (Element)', async function xml10 (t) {
+  var { users, xml0 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  xml0.insert(0, [Y.XmlElement('A'), Y.XmlElement('B'), Y.XmlElement('C')])
+  await wait()
+  xml0.delete(1, 2)
+  await wait()
+  t.assert(xml0.length === 1, 'check length (y)')
+  t.assert(dom0.childNodes.length === 1, 'check length (dom)')
+  t.assert(dom0.childNodes[0].nodeName === 'A', 'check content')
+  await compareUsers(t, users)
+})
+
+test('delete consecutive (2) (Element)', async function xml11 (t) {
+  var { users, xml0 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  xml0.insert(0, [Y.XmlElement('A'), Y.XmlElement('B'), Y.XmlElement('C')])
+  await wait()
+  xml0.delete(0, 1)
+  xml0.delete(1, 1)
+  await wait()
+  t.assert(xml0.length === 1, 'check length (y)')
+  t.assert(dom0.childNodes.length === 1, 'check length (dom)')
+  t.assert(dom0.childNodes[0].nodeName === 'B', 'check content')
+  await compareUsers(t, users)
+})
+
+test('Receive a bunch of elements (with disconnect)', async function xml12 (t) {
+  var { users, xml0, xml1 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  let dom1 = xml1.getDom()
+  users[1].disconnect()
+  xml0.insert(0, [Y.XmlElement('A'), Y.XmlElement('B'), Y.XmlElement('C')])
+  xml0.insert(0, [Y.XmlElement('X'), Y.XmlElement('Y'), Y.XmlElement('Z')])
+  await users[1].reconnect()
+  await flushAll(t, users)
+  t.assert(xml0.length === 6, 'check length (y)')
+  t.assert(xml1.length === 6, 'check length (y) (reconnected user)')
+  t.assert(dom0.childNodes.length === 6, 'check length (dom)')
+  t.assert(dom1.childNodes.length === 6, 'check length (dom) (reconnected user)')
+  await compareUsers(t, users)
+})
+
+test('move element to a different position', async function xml13 (t) {
+  var { users, xml0, xml1 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  let dom1 = xml1.getDom()
+  dom0.append(document.createElement('div'))
+  dom0.append(document.createElement('h1'))
+  await flushAll(t, users)
+  dom1.insertBefore(dom1.childNodes[0], null)
+  t.assert(dom1.childNodes[0].nodeName === 'H1', 'div was deleted (user 0)')
+  t.assert(dom1.childNodes[1].nodeName === 'DIV', 'div was moved to the correct position (user 0)')
+  t.assert(dom1.childNodes[0].nodeName === 'H1', 'div was deleted (user 1)')
+  t.assert(dom1.childNodes[1].nodeName === 'DIV', 'div was moved to the correct position (user 1)')
+  await compareUsers(t, users)
+})
+
+test('filter node', async function xml14 (t) {
+  var { users, xml0, xml1 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  let dom1 = xml1.getDom()
+  let domFilter = (node, attrs) => {
+    if (node.nodeName === 'H1') {
+      return null
+    } else {
+      return attrs
+    }
+  }
+  xml0.setDomFilter(domFilter)
+  xml1.setDomFilter(domFilter)
+  dom0.append(document.createElement('div'))
+  dom0.append(document.createElement('h1'))
+  await flushAll(t, users)
+  t.assert(dom1.childNodes.length === 1, 'Only one node was not transmitted')
+  t.assert(dom1.childNodes[0].nodeName === 'DIV', 'div node was transmitted')
+  await compareUsers(t, users)
+})
+
+test('filter attribute', async function xml15 (t) {
+  var { users, xml0, xml1 } = await initArrays(t, { users: 3 })
+  let dom0 = xml0.getDom()
+  let dom1 = xml1.getDom()
+  let domFilter = (node, attrs) => {
+    return attrs.filter(name => name !== 'hidden')
+  }
+  xml0.setDomFilter(domFilter)
+  xml1.setDomFilter(domFilter)
+  dom0.setAttribute('hidden', 'true')
+  dom0.setAttribute('style', 'height: 30px')
+  dom0.setAttribute('data-me', '77')
+  await flushAll(t, users)
+  t.assert(dom0.getAttribute('hidden') === 'true', 'User 0 still has the attribute')
+  t.assert(dom1.getAttribute('hidden') == null, 'User 1 did not receive update')
+  t.assert(dom1.getAttribute('style') === 'height: 30px', 'User 1 received style update')
+  t.assert(dom1.getAttribute('data-me') === '77', 'User 1 received data update')
+  await compareUsers(t, users)
+})
+
+// TODO: move elements
+var xmlTransactions = [
+  function attributeChange (t, user, chance) {
+    user.share.xml.getDom().setAttribute(chance.word(), chance.word())
+  },
+  function attributeChangeHidden (t, user, chance) {
+    user.share.xml.getDom().setAttribute('hidden', chance.word())
+  },
+  function insertText (t, user, chance) {
+    let dom = user.share.xml.getDom()
+    var succ = dom.children.length > 0 ? chance.pickone(dom.children) : null
+    dom.insertBefore(document.createTextNode(chance.word()), succ)
+  },
+  function insertHiddenDom (t, user, chance) {
+    let dom = user.share.xml.getDom()
+    var succ = dom.children.length > 0 ? chance.pickone(dom.children) : null
+    dom.insertBefore(document.createElement('hidden'), succ)
+  },
+  function insertDom (t, user, chance) {
+    let dom = user.share.xml.getDom()
+    var succ = dom.children.length > 0 ? chance.pickone(dom.children) : null
+    dom.insertBefore(document.createElement(chance.word()), succ)
+  },
+  function deleteChild (t, user, chance) {
+    let dom = user.share.xml.getDom()
+    if (dom.childNodes.length > 0) {
+      var d = chance.pickone(dom.childNodes)
+      d.remove()
+    }
+  },
+  function insertTextSecondLayer (t, user, chance) {
+    let dom = user.share.xml.getDom()
+    if (dom.children.length > 0) {
+      let dom2 = chance.pickone(dom.children)
+      let succ = dom2.childNodes.length > 0 ? chance.pickone(dom2.childNodes) : null
+      dom2.insertBefore(document.createTextNode(chance.word()), succ)
+    }
+  },
+  function insertDomSecondLayer (t, user, chance) {
+    let dom = user.share.xml.getDom()
+    if (dom.children.length > 0) {
+      let dom2 = chance.pickone(dom.children)
+      let succ = dom2.childNodes.length > 0 ? chance.pickone(dom2.childNodes) : null
+      dom2.insertBefore(document.createElement(chance.word()), succ)
+    }
+  },
+  function deleteChildSecondLayer (t, user, chance) {
+    let dom = user.share.xml.getDom()
+    if (dom.children.length > 0) {
+      let dom2 = chance.pickone(dom.children)
+      if (dom2.childNodes.length > 0) {
+        let d = chance.pickone(dom2.childNodes)
+        d.remove()
+      }
+    }
+  }
+]
+
+test('y-xml: Random tests (10)', async function xmlRandom10 (t) {
+  await applyRandomTests(t, xmlTransactions, 10)
+})
+
+test('y-xml: Random tests (42)', async function xmlRandom42 (t) {
+  await applyRandomTests(t, xmlTransactions, 42)
+})
+
+test('y-xml: Random tests (43)', async function xmlRandom43 (t) {
+  await applyRandomTests(t, xmlTransactions, 43)
+})
+
+test('y-xml: Random tests (44)', async function xmlRandom44 (t) {
+  await applyRandomTests(t, xmlTransactions, 44)
+})
+
+test('y-xml: Random tests (45)', async function xmlRandom45 (t) {
+  await applyRandomTests(t, xmlTransactions, 45)
+})
+
+test('y-xml: Random tests (46)', async function xmlRandom46 (t) {
+  await applyRandomTests(t, xmlTransactions, 46)
+})
+
+test('y-xml: Random tests (47)', async function xmlRandom47 (t) {
+  await applyRandomTests(t, xmlTransactions, 47)
+})
--- a/tests-lib/helper.js
+++ b/tests-lib/helper.js
@@ -1,23 +1,24 @@

 import _Y from '../../yjs/src/y.js'

-import yMemory from '../../y-memory/src/y-memory.js'
 import yArray from '../../y-array/src/y-array.js'
-import yMap from '../../y-map/src/Map.js'
+import yText from '../../y-text/src/y-text.js'
+import yMap from '../../y-map/src/y-map.js'
+import yXml from '../../y-xml/src/y-xml.js'
 import yTest from './test-connector.js'

 import Chance from 'chance'

 export let Y = _Y

-Y.extend(yMemory, yArray, yMap, yTest)
+Y.extend(yArray, yText, yMap, yTest, yXml)

 export var database = { name: 'memory' }
 export var connector = { name: 'test', url: 'http://localhost:1234' }

-function * getStateSet () {
+function getStateSet () {
  var ss = {}
-  yield * this.ss.iterate(this, null, null, function * (n) {
+  this.ss.iterate(this, null, null, function (n) {
    var user = n.id[0]
    var clock = n.clock
    ss[user] = clock
@@ -25,9 +26,9 @@ function * getStateSet () {
  return ss
 }

-function * getDeleteSet () {
+function getDeleteSet () {
  var ds = {}
-  yield * this.ds.iterate(this, null, null, function * (n) {
+  this.ds.iterate(this, null, null, function (n) {
    var user = n.id[0]
    var counter = n.id[1]
    var len = n.len
@@ -47,6 +48,39 @@ export async function garbageCollectUsers (t, users) {
  await Promise.all(users.map(u => u.db.emptyGarbageCollector()))
 }

+export function attrsObject (dom) {
+  let keys = []
+  let yxml = dom.__yxml
+  for (let i = 0; i < dom.attributes.length; i++) {
+    keys.push(dom.attributes[i].name)
+  }
+  keys = yxml._domFilter(dom, keys)
+  let obj = {}
+  for (let i = 0; i < keys.length; i++) {
+    let key = keys[i]
+    obj[key] = dom.getAttribute(key)
+  }
+  return obj
+}
+
+export function domToJson (dom) {
+  if (dom.nodeType === document.TEXT_NODE) {
+    return dom.textContent
+  } else if (dom.nodeType === document.ELEMENT_NODE) {
+    let attributes = attrsObject(dom, dom.__yxml)
+    let children = Array.from(dom.childNodes.values())
+      .filter(d => d.__yxml !== false)
+      .map(domToJson)
+    return {
+      name: dom.nodeName,
+      children: children,
+      attributes: attributes
+    }
+  } else {
+    throw new Error('Unsupported node type')
+  }
+}
+
 /*
 * 1. reconnect and flush all
 * 2. user 0 gc
@@ -73,6 +107,7 @@ export async function compareUsers (t, users) {
  }
  var userMapOneValues = users.map(u => u.share.map.get('one')).map(valueToComparable)
  var userMapTwoValues = users.map(u => u.share.map.get('two')).map(valueToComparable)
+  var userXmlValues = users.map(u => u.share.xml.getDom()).map(domToJson)

  await users[0].db.garbageCollect()
  await users[0].db.garbageCollect()
@@ -98,9 +133,9 @@ export async function compareUsers (t, users) {
  let filterDeletedOps = users.every(u => u.db.gc === false)
  var data = await Promise.all(users.map(async (u) => {
    var data = {}
-    u.db.requestTransaction(function * () {
+    u.db.requestTransaction(function () {
      let ops = []
-      yield * this.os.iterate(this, null, null, function * (op) {
+      this.os.iterate(this, null, null, function (op) {
        ops.push(Y.Struct[op.struct].encode(op))
      })

@@ -114,7 +149,7 @@ export async function compareUsers (t, users) {
          as they might have been split up differently..
         */
        if (filterDeletedOps) {
-          let opIsDeleted = yield * this.isDeleted(op.id)
+          let opIsDeleted = this.isDeleted(op.id)
          if (!opIsDeleted) {
            data.os[JSON.stringify(op.id)] = op
          }
@@ -122,8 +157,8 @@ export async function compareUsers (t, users) {
          data.os[JSON.stringify(op.id)] = op
        }
      }
-      data.ds = yield * getDeleteSet.apply(this)
-      data.ss = yield * getStateSet.apply(this)
+      data.ds = getDeleteSet.apply(this)
+      data.ss = getStateSet.apply(this)
    })
    await u.db.whenTransactionsFinished()
    return data
@@ -133,6 +168,7 @@ export async function compareUsers (t, users) {
      t.compare(userArrayValues[i], userArrayValues[i + 1], 'array types')
      t.compare(userMapOneValues[i], userMapOneValues[i + 1], 'map types (propery "one")')
      t.compare(userMapTwoValues[i], userMapTwoValues[i + 1], 'map types (propery "two")')
+      t.compare(userXmlValues[i], userXmlValues[i + 1], 'xml types')
      t.compare(data[i].os, data[i + 1].os, 'os')
      t.compare(data[i].ds, data[i + 1].ds, 'ds')
      t.compare(data[i].ss, data[i + 1].ss, 'ss')
@@ -147,7 +183,7 @@ export async function initArrays (t, opts) {
  var result = {
    users: []
  }
-  var share = Object.assign({ flushHelper: 'Map', array: 'Array', map: 'Map' }, opts.share)
+  var share = Object.assign({ flushHelper: 'Map', array: 'Array', map: 'Map', xml: 'XmlElement("div")' }, opts.share)
  var chance = opts.chance || new Chance(t.getSeed() * 1000000000)
  var conn = Object.assign({ room: 'debugging_' + t.name, generateUserId: false, testContext: t, chance }, connector)
  for (let i = 0; i < opts.users; i++) {
@@ -170,6 +206,13 @@ export async function initArrays (t, opts) {
    for (let name in share) {
      result[name + i] = y.share[name]
    }
+    y.share.xml.setDomFilter(function (d, attrs) {
+      if (d.nodeName === 'HIDDEN') {
+        return null
+      } else {
+        return attrs.filter(a => a !== 'hidden')
+      }
+    })
  }
  result.array0.delete(0, result.array0.length)
  if (result.users[0].connector.testRoom != null) {
--- a/y.js
+++ b/y.js
--- a/y.js.map
+++ b/y.js.map
--- a/y.node.js
+++ b/y.node.js
--- a/y.node.js.map
+++ b/y.node.js.map
--- a/y.test.js
+++ b/y.test.js
--- a/y.test.js.map
+++ b/y.test.js.map
Author	SHA1	Message	Date
Kevin Jahns	e6badf98a2	v13.0.0-22 -- distribution files	2017-10-07 00:46:32 +02:00
Kevin Jahns	d9ee67d2f3	13.0.0-22	2017-10-07 00:42:06 +02:00
Kevin Jahns	791f6c12f0	add indexeddb example	2017-10-07 00:40:34 +02:00
Kevin Jahns	23d019c244	add writeObjectToYMap and writeArrayToYArray helper utilities	2017-10-07 00:39:26 +02:00
Kevin Jahns	c8ca80d15f	13.0.0-21	2017-10-02 15:52:11 +02:00
Kevin Jahns	be282c8338	fix lint	2017-10-02 15:50:56 +02:00
Kevin Jahns	829a094c6d	check for responsiveness when maxBufferSize is set	2017-10-02 15:45:23 +02:00
Kevin Jahns	725273167e	13.0.0-20	2017-09-29 22:34:18 +02:00
Kevin Jahns	581264c5e3	implement relative position helper	2017-09-29 22:33:28 +02:00
Kevin Jahns	be537c9f8c	13.0.0-19	2017-09-26 21:53:01 +02:00
Kevin Jahns	4028eee39d	implemented chunked broadcast of updates	2017-09-26 21:52:07 +02:00
Kevin Jahns	0e3e561ec7	13.0.0-18	2017-09-20 11:34:03 +02:00
Kevin Jahns	7df46cb731	Merge branch 'master' of github.com:y-js/yjs	2017-09-20 11:30:24 +02:00
Kevin Jahns	40fb16ef32	catch y-* related errors	2017-09-20 11:29:13 +02:00
Kevin Jahns	ada5d36cd5	add more y-xml tests	2017-09-19 03:16:48 +02:00
Kevin Jahns	f537a43e29	implement tests for dom filter	2017-09-18 22:14:45 +02:00
Kevin Jahns	3a305fb228	13.0.0-17	2017-09-11 17:38:21 +02:00
Kevin Jahns	1afdab376d	fix linting	2017-09-11 17:37:39 +02:00
Kevin Jahns	526c862071	added test case for moving nodes	2017-09-11 17:35:20 +02:00
Kevin Jahns	fdbb558ce2	persistence db fixes	2017-09-11 16:02:19 +02:00
Kevin Jahns	76ad58bb59	fix example dist script	2017-09-07 23:02:19 +02:00
Kevin Jahns	c88a813bb0	fix tests by removing y-memory include	2017-09-06 20:52:52 +02:00
Kevin Jahns	ccf6d86c98	removed generators	2017-09-06 20:10:38 +02:00
Kevin Jahns	6b5c02f1ce	13.0.0-16	2017-08-26 01:11:31 +02:00
Kevin Jahns	2be6e935a4	fix lint in xml tests	2017-08-26 01:10:50 +02:00
Kevin Jahns	0ddf3bf742	Y.Xml renamed to Y.XmlElement	2017-08-25 20:35:17 +02:00
Kevin Jahns	5f29724578	merge textarea example	2017-08-24 14:46:16 +02:00
Kevin Jahns	ab6cde07e6	Implemented Xml Struct	2017-08-24 14:44:40 +02:00
Kevin Jahns	0455eaa8ad	13.0.0-15	2017-08-14 15:53:54 +02:00
Kevin Jahns	9ed7e15d0f	13.0.0-14	2017-08-14 15:49:15 +02:00
Kevin Jahns	6e633d0bd9	lint	2017-08-14 15:41:37 +02:00
Kevin Jahns	e16195cb54	implement timeout for creating Yjs instance	2017-08-14 15:39:17 +02:00