Современные веб-приложения

// find the number to increment in the path.
    function determinePath(path){

     if ( path.match(/^(.*?)\b2\b(.*?$)/) ){  
          path = path.match(/^(.*?)\b2\b(.*?$)/).slice(1);
          
      // if there is any 2 in the url at all.    
      } else if (path.match(/^(.*?)2(.*?$)/)){
        
          // page= is used in django:
          //   http://www.infinite-scroll.com/changelog/comment-page-1/#comment-127
          if ( path.match(/^(.*?page=)2(\/.*|$)/) ){
            path = path.match(/^(.*?page=)2(\/.*|$)/).slice(1);
            return path;
          }
          
          debug('Trying backup next selector parse technique. Treacherous waters here, matey.');
          path = path.match(/^(.*?)2(.*?$)/).slice(1);
      } else {
          
        // page= is used in drupal too but second page is page=1 not page=2:
        // thx Jerod Fritz, vladikoff
        if (path.match(/^(.*?page=)1(\/.*|$)/)) {
          path = path.match(/^(.*?page=)1(\/.*|$)/).slice(1);
          return path;
        }  

        if ($.isFunction(opts.pathParse)){
          return [path];
        } else {
          debug('Sorry, we couldn\'t parse your Next (Previous Posts) URL. Verify your the css selector points to the correct A tag. If you still get this error: yell, scream, and kindly ask for help at infinite-scroll.com.');    
          props.isInvalidPage = true;  //prevent it from running on this page.
        }
      }
      return path;
    }