diff --git a/doc/todo/dependency_types.mdwn b/doc/todo/dependency_types.mdwn index 6218222f7..58b5ee955 100644 --- a/doc/todo/dependency_types.mdwn +++ b/doc/todo/dependency_types.mdwn @@ -10,7 +10,7 @@ whenever a matching dependency is added, removed, or *modified*. But a great many things don't care about the modification case, and often cause unnecessary page rebuilds: -* meta only cares if the pages are added or removed. Content change does +* map only cares if the pages are added or removed. Content change does not matter (unless show=title is used). * brokenlinks, orphans, pagecount, ditto (generally) * inline in archive mode cares about page title, author changing, but @@ -128,14 +128,11 @@ I implemented the above in a branch. Then I found some problems: -* pagestats is often used with a pagespec that uses `tagged()`. - A pure contentless dependency does not work for that, it needs to look - at link info. -* orphans and brokenlinks cannot use contentless dependencies because they - need to update when links change. * Something simple like pagecount, that seems like it could use a contentless dependency, can have a pagespec that uses metadata, like `author()` or `copyright()`. +* pagestats, orphans and brokenlinks cannot use contentless dependencies + because they need to update when links change. Now I'm thinking about having a contentless dependency look at page metadata, and fire if the metadata changes. And it seems links should @@ -146,7 +143,14 @@ It's easy to see when a page's links change, since there is `%oldlinks`. To see when metadata is changed is harder, since it's stored in the pagestate by the meta plugin. -(Alternative: Make add_depends look at the pagespec. Ie, if it is a simple -page name, or a glob, we know a contentless dependency can be valid. -If's more complex, convert the dependency from contentless to full. Finding -a non-ad-hoc, non-sucky way to do that could be hard.) +Quick alternative: Make add_depends look at the pagespec. Ie, if it +is a simple page name, or a glob, we know a contentless dependency +can be valid. If's more complex, convert the dependency from +contentless to full. + +There is a lot to dislike about this method. Its parsing of the +pagespec, as currently implemented, does not let plugins add new types of +pagespecs that are contentless. Its pagespec parsing is also subject to +false negatives (though these should be somewhat rare, and no false +positives). Still, it does work, and it makes things like simple maps and +pagecounts much more efficient.