PageSpec should match against. If not passed, relative PageSpecs will match
relative to the top of the wiki.
-If the PageSpec fails to match, it may return a IkiWiki::FailReason object,
-which evaluates to false in a boolean context, but in a string context,
-evaulates to the reason the PageSpec failed to match.
-
#### `bestlink($$)`
Given a page and the text of a link on the page, determine which
how it will be accessed in a [[PageSpec]]. The function will be passed
two parameters: The name of the page being matched, and the thing to match
against. It may also be passed additional, named parameters. It should return
-true if the match succeeds, and either false or a IkiWiki::FailReason object
-if the match fails.
+a IkiWiki::SuccessReason object if the match succeeds, or an
+IkiWiki::FailReason object if the match fails.