Markdium-What is a Mixin?

Markdium-JavaScript.js

// defining the Mixin
export const LoggingMixin = superclass =>
  class LoggingMixin extends superclass {
    // logging logic
  };

class Page {}
// applying a Mixin
class PageRed extends LoggingMixin(Page) {}
class PageGreen extends LoggingMixin(Page) {}
class PageBlue extends Page {}