How to lazyload Javascript using LocalStorage

/*! Lazy Function by Fineshop Design | uses HTML5 localStorage */
(function(e){var t=[];function n(e){"function"==typeof e&&(n.lazied||t.executed?e.call(window,{type:"LOCAL_STORAGE"}):t.push(e))}function o(){0==document.documentElement.scrollTop&&0==document.body.scrollTop||(t.execute({type:"SCROLL"}),window.removeEventListener("scroll",o))}function c(){t.execute({type:"CLICK"}),document.body.removeEventListener("click",c)}function d(){n.lazied||t.executed||(document.body.addEventListener("click",c),window.addEventListener("scroll",o),o()),document.removeEventListener("DOMContentLoaded",d)}t.executed=!1,n.lazied=localStorage.getItem(e.key)===e.value,t.execute=function(){if(!1===this.executed){this.executed=!0,n.lazied=!0,localStorage.getItem(e.key)!==e.value&&localStorage.setItem(e.key,e.value);for(let e=0;e<this.length;e++)"function"==typeof this[e]&&this[e].apply(window,arguments),this.splice(e,1),e--}},"complete"===document.readyState||"loading"!==document.readyState||null!==document.body?d():document.addEventListener("DOMContentLoaded",d),this[e.name]=n}).call(this,{name:"Lazy",key:"LOCAL_LAZY",value:"true"});

Example

function lazyCallback (arg) {
  // Load your JS dynamically
  // Make HTTP requests
  console.log(arg.type) // Probably: SCROLL, LOCAL_STORAGE, CLICK
}
Lazy(lazyCallback);