From bd958f91a2b71761e9aa20fa25a6702dab3b4b8d Mon Sep 17 00:00:00 2001 From: Joey Hess Date: Sat, 3 Oct 2009 17:38:47 -0400 Subject: [PATCH] did a scratch implementation of dependancy types, but found it more complex --- doc/todo/dependency_types.mdwn | 37 +++++++++++++++++++++++++++++----- 1 file changed, 32 insertions(+), 5 deletions(-) diff --git a/doc/todo/dependency_types.mdwn b/doc/todo/dependency_types.mdwn index 215a65c8a..6218222f7 100644 --- a/doc/todo/dependency_types.mdwn +++ b/doc/todo/dependency_types.mdwn @@ -12,7 +12,7 @@ unnecessary page rebuilds: * meta only cares if the pages are added or removed. Content change does not matter (unless show=title is used). -* brokenlinks, orphans, pagecount, ditto +* brokenlinks, orphans, pagecount, ditto (generally) * inline in archive mode cares about page title, author changing, but not content. (Ditto for meta with show=title.) * Causes extra work when solving the [[bugs/transitive_dependencies]] @@ -109,9 +109,6 @@ I propose the following. --[[Joey]] * `add_depends` defaults to adding a regular ("full") dependency, as before. (So nothing breaks.) * `add_depends($page, $spec, content => 0)` adds an contentless dependency. -* Contentless dependencies are stored in `%depends_contentless` and - `%depends_contentless_simple`, which are stored in the index similarly - to the existing hashes. * `refresh` only looks at added/removed pages when resolving contentless dependencies. @@ -121,5 +118,35 @@ to the two types he talks about above, but I hope are close enough that they can be used. This doesn't deal with the stuff that only depend on the metadata of a -page, as collected in the scan pass, changing. But it does leave a window +page, as collected in the scan pass, changing. But it does leave a window open for adding such a dependency type later. + +---- + +I implemented the above in a branch. +[[!template id=gitbranch branch=origin/dependency-types author="[[joey]]"]] + +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()`. + +Now I'm thinking about having a contentless dependency look at page +metadata, and fire if the metadata changes. And it seems links should +either be included in that, or there should be a way to make a dependency +that fires when a page's links change. (And what about backlinks?) + +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.)