Code internals

There are two global variables:

• numbers : an array where we save the unique code assigned to each post by usign the span tag;
  
• dates : a hash which has the post numbers as keys and their associated dates as values.
  

There are three functions in the script:

• showcategory(tag): check for the tag in all posts, show the hits and hide the rest. Furthermore, show the dates for the hits;
• listcategory(postid): list the categories for the current post;
• sidebarcategories(tag): sort and list all the categories in the document;