var sel_top = document.getElementById("buffers_top");

CodeMirror.on(sel_top, "change", function() {

  selectBuffer(ed_top, sel_top.options[sel_top.selectedIndex].value);

});

​

var sel_bot = document.getElementById("buffers_bot");

CodeMirror.on(sel_bot, "change", function() {

  selectBuffer(ed_bot, sel_bot.options[sel_bot.selectedIndex].value);

});

​

var buffers = {};

​

function openBuffer(name, text, mode) {

  buffers[name] = CodeMirror.Doc(text, mode);

  var opt = document.createElement("option");

  opt.appendChild(document.createTextNode(name));

  sel_top.appendChild(opt);

  sel_bot.appendChild(opt.cloneNode(true));

}

​

function newBuf(where) {

  var name = prompt("Name for the buffer", "*scratch*");

  if (name == null) return;

  if (buffers.hasOwnProperty(name)) {

    alert("There's already a buffer by that name.");

    return;

  }

  openBuffer(name, "", "javascript");