This template is made to be used as the default for the outer call of a navlist page; see Template:Navlist/Doc. It provides a warning notice identifying the page as a navlist, wikilinking to the navlist documentation and to the book's main page; and rudimentary echoing of the data in the navlist. It only works for the outer call; it would not behave reasonably for inner calls, and thus is not a map template.
For example, sample navlist Template:Navlist/Doc/A looks like this:
|This page is a navlist, a representation of the table of contents of a book, apparently the Template:Navlist wikibook.
The format is documented at Template:Navlist/Doc.