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   <title>Node Editor</title>

   <div id="nodeEditor" class="node-editor"></div>
   <a target="_blank" href="" class="alert">A new version of the library under the name Rete.js is available</a>



                html, body{
   height: 100%;
   margin: 0;

   position: relative;
  height: 100%

    background: #96b38a

.control input {
   width: 150px

.alert {
   position: absolute;
   left: 0;
   top: 0;
   width: 100%;
   background: rgba(255, 30,3, 0.7);
   color: white;
   padding: 1%;
   font-size: 120%;
   font-family: monospace;
   text-decoration: none;

.alert:hover {
   color: #ffcccc;


                var numSocket = new D3NE.Socket("number", "Number value", "hint");

var componentNum = new D3NE.Component("Number", {
   builder(node) {
      var out1 = new D3NE.Output("Number", numSocket);
      var numControl = new D3NE.Control('<input type="number">',
         (el, c) => {
            el.value = c.getData('num') || 1;
            function upd() {
               c.putData("num", parseFloat(el.value));

            el.addEventListener("input", ()=>{
            el.addEventListener("mousedown", function(e){e.stopPropagation()});// prevent node movement when selecting text in the input field

      return node.addControl(numControl).addOutput(out1);
   worker(node, inputs, outputs) {
      outputs[0] =;

var componentAdd = new D3NE.Component("Add", {
   builder(node) {
      var inp1 = new D3NE.Input("Number", numSocket);
      var inp2 = new D3NE.Input("Number", numSocket);
      var out = new D3NE.Output("Number", numSocket);

      var numControl = new D3NE.Control(
         '<input readonly type="number">',
         (el, control) => {
            control.setValue = val => {
               el.value = val;

      return node
   worker(node, inputs, outputs) {
      var sum = inputs[0][0] + inputs[1][0];
      editor.nodes.find(n => ==[0].setValue(sum);
      outputs[0] = sum;

var menu = new D3NE.ContextMenu({
   Values: {
      Value: componentNum,
      Action: function() {
   Add: componentAdd

var container = document.getElementById("nodeEditor");
var components = [componentNum, componentAdd];
var editor = new D3NE.NodeEditor("demo@0.1.0", container, components, menu);

var nn = componentNum.newNode(); = 2;
var n1 = componentNum.builder(nn);
var n2 = componentNum.builder(componentNum.newNode());
var add = componentAdd.builder(componentAdd.newNode());

n1.position = [80, 200];
n2.position = [80, 400];
add.position = [500, 240];

editor.connect(n1.outputs[0], add.inputs[0]);
editor.connect(n2.outputs[0], add.inputs[1]);

//  editor.selectNode(tnode);

var engine = new D3NE.Engine("demo@0.1.0", components);

editor.eventListener.on("change", async function() {
   await engine.abort();
   await engine.process(editor.toJSON());