Coding text files as Markdown

[Greg Raven]

Can anyone (cough, cough) elaborate on the use of the "coding" directive at the top of text files, such as is seen at the top of the Read Me.txt file in the BBEdit Application Support folder?

    <!-- -*- coding: utf-8; mode: markdown; version: 5; -*- -->

From what I can tell, it:

1. instructs BBEdit to preview the file as if it were a Markdown file.
2. instructs BBEdit to observe Markdown in that file
3. allows the creator of the file to insert some HTML "head" elements before the start of "body" content (excluding a "title" tag)
4. renders (in Preview, at least) an HTML page complete with HTML5 doctype declaration and utf-8 character set
5. renders (in Preview, at least) any DefaultTemplate and DefaultCSS applied to Markdown previews
6. renders (in Preview, at least) any manually-applied template and/or CSS

The cut-off between the "head" content and the "body" content seems to be the last line at the top of the file that is enclosed by an HTML tag (as opposed to starting the "body" content at the first "h1" tag or something similar).