jQuery script to manage rollover effect on img elements with a '.hoverable' class and two images (one with -normal and one with -hover suffix)

imgrollover.js

//  init rollovers on images
imgRollover: function() {

        var $app = this;
        
        $.each($app.$hoverable, function(index, val) {
            var $this = $(this);
        
            //  if the hoverable object is <img>
            if (typeof $this === 'object' && $this.is("img")) {
                var $obj = $this;
            }
        
            //  if the hoverable object contains any <img>
            if (typeof $obj === 'undefined' && !!$this.children("img").length) {
                var $obj = $this.children("img");
            }
        
            if (typeof $obj !== 'undefined' && !!$obj.length) {
                $.each($obj, function(index, val) {
                    var $img = $(this);
        
                    if (typeof $img === 'object') {
                        var normal_src  = $img.attr("src"),
                            hover_src   = $img.attr("src").replace("-normal.", "-hover.");
        
                        if (!!normal_src.length) {
                            $this.hover(function(evt) {
                                console.log("Over");
                                $img.attr("src", hover_src);
                            }, function(evt) {
                                console.log("Leave");
                                $img.attr("src", normal_src);                            
                            });
                        }
                    }
                });
            } else {
                return false;
            }
        });
},