All of the features (except the first) are provided by a simple templating system that uses ` (backtick) as the only metacharacter. This was chosen because it is a character that is not useful in JavaScript nor HTML.

Only in the Free Nodelet, `id` gets replaced with the current node's node_id. `title` gets replaced with the current node's title. If using the title in HTML (almost always), use `title&` instead to get the title with &, <, >, [, and ] characters escaped as HTML entities. To use a title in a URL, use `title%` to have it URL-escaped (using %xx).

The following items get expanded if put between a pair of backticks (`) in the Free Nodelet:

• id - current node's ID
• title - current node's title
• author_id - current node's author's user ID number
• author_name - current node's author's name
• author_title - same as author_name ("title" of their home node)
• user_id - your ID (useful for writing macros that another user can paste into their nodelet)
• user_name - your monk name
• user_title - same as user_name
• _arg - the value of the CGI parameter '_arg' or 'arg' ("arg" can be anything, but the leading _ is required).

Each of the above can have a & or % on the end (just before the closing backtick). Other items like root_id, root_title, sect_id, and sect_title may be added in future. You don't need to use & nor % on *id items, since they expand to just digits and digits don't need to be escaped.

The above expansions happen before [...] links are processed, so you can make a link like [id://`id`|Bookmark node `id`].

The following substitutions are also made:

• `[ becomes [
• `] becomes ]
• `` becomes `
• ``` becomes ``
• ```` becomes ```
• etc.

Note that `[ gets expanded in such a way that the resulting [ will not be processed as a PerlMonk's link specification. So the resulting [ can be part of some JavaScript. Inside of HTML comments, either `[ or just [ can be used.

Note that "HTML comments" at PerlMonks simply start with "<!--" and simply end with "-->". In real HTML comments, whitespace is allowed inside these start/end sequences and occurrences of "--" inside the comments have special meaning. Since the Free Nodelet's HTML is not filtered by PerlMonks, if you put "--" inside your HTML comments there, you might "confuse" your browser, but PerlMonks doesn't care about any appearances of "--" in your HTML comments when it comes to deciding where to not process [...] as a link.

A `_foo` gets expanded to whatever the _foo parameter was set to in the URL (or POST) used to fetch the page, such as via ;_foo=bar. If the no "_foo" parameter exists, then the value of the "foo" parameter is used instead. If not even a "foo" parameter exists, then the item is left as `_foo`, just as is done with any unrecognized template-like item.