For Cody

gistfile1.js

/*!
 * jQuery.preloadImg
 * description: cache images via $.preloadImg(['src','src']) or $('img').preloadImg()
 * author: Cody Lindley
 */

(function($) {
  
  // Internal cache of image src values.
  var cache = {};
  
  $.preloadImages = function( arr ) {
    // For each passed image src value,
    $.each( arr, function(i,src){
      
      // If that value exists and isn't in the cache,
      if ( src && !cache[ src ] ) {
        
        // Preload the image.
        var img = new Image();
        img.src = src;
        
        // Update the cache.
        cache[ src ] = img;
      }
      
    });
  };
  
  $.fn.preloadImages = function() {
    // If the length of the selected elements is non-zero, call $.preloadImages
    // with an array containing all image src values.
    this.length && $.preloadImages( $.map(this, function(elem){
      return elem.src;
    }) );
    
    // Return the original jQuery collection.
    return this;
  };
  
})(jQuery);

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