This hook is called early in the process of building the wiki, and is used
as a first pass scan of the page, to collect metadata about the page. It's
-mostly used to scan the page for [[WikiLinks|ikiwiki/WikiLink]], and add them to `%links`.
-Present in IkiWiki 2.40 and later.
+mostly used to scan the page for [[WikiLinks|ikiwiki/WikiLink]], and add
+them to `%links`. Present in IkiWiki 2.40 and later.
The function is passed named parameters "page" and "content". Its return
value is ignored.
If `hook` is passed an optional "scan" parameter, set to a true value, this
makes the hook be called during the preliminary scan that ikiwiki makes of
updated pages, before begining to render pages. This should be done if the
-hook modifies data in `%links`. Note that doing so will make the hook be
-run twice per page build, so avoid doing it for expensive hooks. (As an
-optimisation, if your preprocessor hook is called in a void context, you
-can assume it's being run in scan mode, and avoid doing expensive things at
-that point.)
+hook modifies data in `%links` (typically by calling `add_link`). Note that
+doing so will make the hook be run twice per page build, so avoid doing it
+for expensive hooks. (As an optimisation, if your preprocessor hook is
+called in a void context, you can assume it's being run in scan mode, and
+avoid doing expensive things at that point.)
Note that if the [[htmlscrubber]] is enabled, html in
preprocessor [[ikiwiki/directive]] output is sanitised, which may limit what
and later.
Plugins that implement linkify must also implement a scan hook, that scans
-for the links on the page and adds them to `%links`.
+for the links on the page and adds them to `%links` (typically by calling
+`add_link`).
### htmlize
PageSpec should match against. If not passed, relative PageSpecs will match
relative to the top of the wiki.
+#### `pagespec_match_list($$;@)`
+
+Passed a reference to a list of page names, and [[ikiwiki/PageSpec]],
+returns the set of pages that match the [[ikiwiki/PageSpec]].
+
+Additional named parameters can be passed, to further limit the match.
+The most often used is "location", which specifies the location the
+PageSpec should match against. If not passed, relative PageSpecs will match
+relative to the top of the wiki.
+
+Unlike pagespec_match, this may throw an error if there is an error in
+the pagespec.
+
#### `bestlink($$)`
Given a page and the text of a link on the page, determine which
filename of the page. For example, `targetpage("foo", "rss", "feed")`
will yield something like `foo/feed.rss`.
+#### `add_link($$)`
+
+This adds a link to `%links`, ensuring that duplicate links are not
+added. Pass it the page that contains the link, and the link text.
+
## Miscellaneous
### Internal use pages
IkiWiki::PageSpec package, that is named `match_foo`, where "foo()" is
how it will be accessed in a [[ikiwiki/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
-a IkiWiki::SuccessReason object if the match succeeds, or an
-IkiWiki::FailReason object if the match fails.
+against. It may also be passed additional, named parameters.
+
+It should return a IkiWiki::SuccessReason object if the match succeeds, or
+an IkiWiki::FailReason object if the match fails. If the match cannot be
+attempted at all, for any page, it can instead return an
+IkiWiki::ErrorReason object explaining why.
### Setup plugins