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Wtyczka służy do pobierania opisu+zdjęcia avatra z twittera, dodatkowo wyświetla czas kiedy wpis był umieszczony. Mam kilka pytań bo nie do końca rozumiem działanie tego skryptu.
1. Co to jest funkcja, klasa, obiekt ? (sry za takie pytanie ale naprawdę mam wątpliwości a chce wiedzieć)
2. Referencja this w this.replace czy donosi się do tego obiektu jQuery $([item.text]) ?
3. Do czego odnosi się referencja this w this.each(function() {returning.push(this.replace(regexp,"<a href=\"$1\">$1</a>"))}); i jakie zastosowanie mają $1, drugi argument funkcji replace to tekst do zastępujący wyrażenie pasujące do regexp więc nie za bardzo to rozumiem.

[JAVASCRIPT] pobierz, plaintext 
(function($) {
 
  $.fn.tweet = function(o){
    var s = {
      username: ["user_name"],              // [string]   required, unless you want to display our tweets. :) it can be an array, just do ["username1","username2","etc"]
      avatar_size: null,                      // [integer]  height and width of avatar if displayed (48px max)
      count: 1,                               // [integer]  how many tweets to display?
      loading_text: null,                     // [string]   optional loading text, displayed while tweets load
      query: null                             // [string]   optional search query
    };
 
    $.fn.extend({
      linkUrl: function() {
        var returning = [];
        var regexp = /((ftp|http|https):\/\/(\w+:{0,1}\w*@)?(\S+)(:[0-9]+)?(\/|\/([\w#!:.?+=&%@!\-\/]))?)/gi;
        this.each(function() {
          returning.push(this.replace(regexp,"<a href=\"$1\">$1</a>"))
        });
        return $(returning);
      },
      linkUser: function() {
        var returning = [];
        var regexp = /[\@]+([A-Za-z0-9-_]+)/gi;
        this.each(function() {
          returning.push(this.replace(regexp,"<a href=\"http://twitter.com/$1\">@$1</a>"))
        });
        return $(returning);
      },
      linkHash: function() {
        var returning = [];
        var regexp = / [\#]+([A-Za-z0-9-_]+)/gi;
        this.each(function() {
          returning.push(this.replace(regexp, ' <a href="http://search.twitter.com/search?q=&tag=$1&lang=all&from='+s.username.join("%2BOR%2B")+'">#$1</a>'))
        });
        return $(returning);
      },
      capAwesome: function() {
        var returning = [];
        this.each(function() {
          returning.push(this.replace(/(a|A)wesome/gi, 'AWESOME'))
        });
        return $(returning);
      },
      capEpic: function() {
        var returning = [];
        this.each(function() {
          returning.push(this.replace(/(e|E)pic/gi, 'EPIC'))
        });
        return $(returning);
      },
      makeHeart: function() {
        var returning = [];
        this.each(function() {
          returning.push(this.replace(/[&lt;]+[3]/gi, "<tt class='heart'>&#x2665;</tt>"))
        });
        return $(returning);
      }
    });
 
    function relative_time(time_value) {
      var parsed_date = Date.parse(time_value);
      var relative_to = (arguments.length > 1) ? arguments[1] : new Date();
      var delta = parseInt((relative_to.getTime() - parsed_date) / 1000);
      if(delta < 60) {
      return 'less than a minute ago';
      } else if(delta < 120) {
      return 'about a minute ago';
      } else if(delta < (45*60)) {
      return (parseInt(delta / 60)).toString() + ' minutes ago';
      } else if(delta < (90*60)) {
      return 'about an hour ago';
      } else if(delta < (24*60*60)) {
      return 'about ' + (parseInt(delta / 3600)).toString() + ' hours ago';
      } else if(delta < (48*60*60)) {
      return '1 day ago';
      } else {
      return (parseInt(delta / 86400)).toString() + ' days ago';
      }
    }
 
    if(o) $.extend(s, o);
    return this.each(function(){
      var list = $('<span class="tweet">').appendTo(this);
      var loading = $('<span class="loading">'+s.loading_text+'</span>');
      if(typeof(s.username) == "string"){
        s.username = [s.username];
      }
 
      var query = '';
      if(s.query) {
        query += 'q='+s.query;
      }
      query += '&q=from:'+s.username.join('%20OR%20from:');
      var url = 'http://search.twitter.com/search.json?&'+query+'&rpp='+s.count+'&callback=?';
      if (s.loading_text) $(this).append(loading);
      $.getJSON(url, function(data){
        if (s.loading_text) loading.remove();
        $.each(data.results, function(i,item){
 
          var avatar_template = '<a class="tweet_avatar" href="http://twitter.com/'+ item.from_user+'"><img src="'+item.profile_image_url+'" height="'+s.avatar_size+'" width="'+s.avatar_size+'" alt="'+item.from_user+'\'s avatar" border="0"/></a>';
          var avatar = (s.avatar_size ? avatar_template : '')
          var date = '<a href="http://twitter.com/'+item.from_user+'/statuses/'+item.id+'" title="view tweet on twitter">'+relative_time(item.created_at)+'</a>';
          var text = '<span class="tweet_text">' +$([item.text]).linkUrl().linkUser().linkHash().makeHeart().capAwesome().capEpic()[0]+ '</span>';
 
          // until we create a template option, arrange the items below to alter a tweet's display.
          list.append(text + '</span>');
		  $(".date").html(relative_time(item.created_at));
		  $(".avatar").html(avatar);
        });
      });
    });
  };
})(jQuery);
[JAVASCRIPT] pobierz, plaintext