as_clindoc() is intended for a single clintable object and extracts all
necessary title and footnote information to apply to the document
clindoc() can accept clintable objects as separate parameters or as a
list of clintable objects. If a single clintable is passed, this function
simply calls as_clindoc() internally.
When a multiple clintable objects are passed to clindoc(), titles and footnotes
should be applied directly to the clindoc object using clin_add_title(),
clin_add_footnote(), or clin_add_footnote_page(). Title and footnote information
on the individual clintable objects will be ignored.