58 lines
2.8 KiB
Markdown
58 lines
2.8 KiB
Markdown
[[!template id=gitbranch branch=GiuseppeBilotta/scanif author="Giuseppe Bilotta"]]
|
|
|
|
When a directive that should be run during scan preprocessing is inside
|
|
an if directive, it doesn't get called because the if preprocessing does
|
|
not run during scan.
|
|
|
|
I've written a simple [[patch]] to fix the issue, currently hosted on the
|
|
scanif branch of my repository. The patch also passes the preview option
|
|
back to the Ikiwiki::preprocess call, making sure that whatever is being
|
|
reprocessed is done so in the same conditions as the original call.
|
|
|
|
> One problem with this is that it has the same dependency-ordering problems
|
|
> as inline-based or pagespec-based trails with my [[plugins/contrib/trail]]
|
|
> plugin: `if` takes a pagespec, but pagespecs aren't guaranteed to match
|
|
> correctly until everything has been scanned (for instance, `link()` might
|
|
> give the wrong results because a page that added or deleted a link hasn't
|
|
> been scanned yet). If you have a clever idea for how to fix this, I'd love
|
|
> to hear it - being able to specify a [[plugins/contrib/trail]] in terms
|
|
> of a sorted pagespec would be useful. --[[smcv]]
|
|
|
|
>> I have a solution to the dependency-ordering problem in a different
|
|
>> branch of my repository, with a post_scan hook mechanism which I use to
|
|
>> be able to sort outer inline pages according to the last modification
|
|
>> date of their nested inline pages. The way I implemented it currently,
|
|
>> though, doesn't use the existing hooks mechanism of ikiwiki (because
|
|
>> it's something which I believe to be more efficiently done the way I
|
|
>> implemented it) so I don't know how likely it is to be included
|
|
>> upstream.
|
|
|
|
>> For what it's worth, I think that my post_scan hook mechanism would work
|
|
>> rather fine with your trail plugin.
|
|
|
|
>>> We discussed this on IRC, and I think it's actually more complicated
|
|
>>> than that: the branch to sort by newest inlined entry wants a
|
|
>>> "pagespecs now work" hook, whereas for trail I want a "sorting now
|
|
>>> works" hook:
|
|
>>>
|
|
>>> * scan
|
|
>>> * pagespecs now work (post-scan)
|
|
>>> * Giuseppe's version of inline can decide what each inline
|
|
>>> contains, and thus decide where they go in `inline(mtime)`
|
|
>>> order
|
|
>>> * pagespecs and sorting now work (pre-render)
|
|
>>> * my trail plugin can decide what each trail contains, and
|
|
>>> also sort them in the right order (which might be
|
|
>>> `inline(mtime)`, so might be undefined until pagespecs work)
|
|
>>> * render
|
|
>>>
|
|
>>> --[[smcv]]
|
|
|
|
>> However, the case of the if
|
|
>> directive is considerably more complicated, because the conditional
|
|
>> can introduce a much stronger feedback effect in the pre/post scanning
|
|
>> dependency. In fact, it's probably possible to build a couple of pages
|
|
>> with vicious conditional dependency circles that would break/unbreak
|
|
>> depending on which pass we are in. And I believe this is an intrinsic
|
|
>> limitation of the system, which cannot be solved at all.
|