[plt-scheme] 'net/url' package: path/param?

(make-path/param "folder" null)

A path/param is just a standard un-special PLT structure type.
(define-struct path/param (path param))

...with a few contracts wrapped around it.

(make-path/param "folder" null) is what you'll use in most cases.
 If you want parameters
(make-path/param "folder" '("param1" "param2" ...)).

To get at the path or parameters it's just path/param-path and
path/param-param. Kind of redundant naming, but better I guess than
thingy-path and thingy-param.

Remember that the URL path is a (listof path/param) so each path/param
only specifies a single element of the path. Also path/param paths are
different from the filesystem specific PLT paths that you get from
(build-path)