// Inheritance
function mixin(c, p) {
for(var k in p) if(p.hasOwnProperty(k)) c[k] = p[k];
}
function inherits(c, p) {
mixin(c.prototype, p.prototype);
function f() { this.constructor = c; }
f.prototype = c._super = p.prototype;
c.prototype = new f();
}
function SubscrForm() {
inherits(SubscrForm, Main);
}
var subscrForm = new SubscrForm();
// http://arjanvandergaag.nl/blog/javascript-class-pattern.html
// https://alexsexton.com/blog/2013/04/understanding-javascript-inheritance/