Detecting Microsoft's edge or spartan with javascript

Question

Is the user agent for Edge or Spartan browsers known already? Can anyone tell me how to detect this browser and diferentiate it from IE in advance of its release?

Answer 1

According to this answer:

// Internet Explorer 6-11
var isIE = /*@cc_on!@*/false || !!document.documentMode;
// Edge 20+
var isEdge = !isIE && !!window.StyleMedia;