ikiwiki/doc/todo/admonitions.mdwn

In the [MoinMoin wiki][], there is this neat little hack called
[Admonitions][] that basically create a `<div>` block with a specific
style out of a certain section of the text.

I couldn't find a way to do this easily in Ikiwiki. On the one hand,
there is no easy way to create div blocks with arbitrary styles (which
is basically what MoinMoin admonitions are). On the other hand, there
are no neat little logos in stylesheets like there are in Moinmoin
either.

It would be great to see this implemented in Ikiwiki. Now, I know I
can make a `<div>` myself, but I am not sure we should encourage users
to inject arbitrary HTML in ikiwiki pages. And even then, we should
add adminition CSS classes to make that easier to use.

Ideally, Ikiwiki would support Pandoc or Github-style fenced blocks
and could abuse those to allow arbitrary styles (and markup!) to kick
in. The [[ikiwiki/directive/format]] directive could also be used, I
guess, but I dislike how it requires all those brackets and quotes and
bangs and all...

-- [[anarcat]]

[MoinMoin wiki]: https://moinmo.in/
[Admonitions]: https://moinmo.in/HelpOnAdmonitions

> ikiwiki's general design is that it supports exactly three forms
> of markup:
>
> * whatever the `htmlize` plugin does
> * as a special ikiwiki-specific extension, \[[wikilinks]]
> * as another special ikiwiki-specific extension, \[[!directives]]
>
> All markup interpretation beyond wikilinks and directives is
> the `htmlize` plugin's responsibility. The `mdwn` plugin
> interprets Markdown, the `rst` plugin interprets
> reStructuredText and so on.
>
> It sounds as though you're asking for a `htmlize` plugin which
> interprets an extended dialect of Markdown:
>
> * standard Markdown (inasmuch as such a thing exists) as usual
> * mapping certain syntax (what?) to "admonitions"
>
> ikiwiki deliberately doesn't implement Markdown parsing, it just
> calls out to one of several Perl implementations of Markdown.
>
> Alternatively, you could have a small plugin that translates
>
>     [[!warning "Do what I say, not as I do."]]
>
> into an appropriate `<div>`. That's the "lightest" form of
> markup that is built into ikiwiki itself.
>
> Alternatively^2, some different hook (I think [[plugins/typography]]
> might use the right one?) could interpret an ad-hoc syntax and
> turn it into a `<div>` either before or after `htmlize` processing.
> However, that would be adding an extra layer of syntax for your
> users to keep track of.
>
> [[templates|ikiwiki/directive/template]] are another way this could
> work:
>
>     \[[!template id=warning text="Do as I say, not as I do."]]
>
> There's a "note" template bundled with ikiwiki already.
>
> --[[smcv]]

>> I think you mean the `htmlize` hook, as I cannot find any `htmlize`
>> plugin.. That said, yeah, i understand the limitations of Ikiwiki
>> here. I guess that the [[ikiwiki/directive/template]] directive is a
>> good workaround, but it's not really shorter to write:
>>
>>     \[[!template id=warning text="Do as I say, not as I do."]]
>>
>> than to write:
>>
>> [[!format txt """<div class="warning">Do as I say, not as I do.</div>"""]]
>>
>> ... in fact, it's actually longer. So short of allowing arbitrary
>> classes *and* fenced blocks, I don't think this can go much
>> further.
>>
>> We *could*, however, import the admonition styles from MoinMoin
>> directly. It would involve importing 5 icons from MoinMoin and
>> creating associated styles. Is that something you would be open to?
>>
>> --[[anarcat]]

>> Looking more at the MoinMoin images, the source (and license!) for
>> them is not quite clear, so they don't make such great targets for
>> inclusion. They are, nevertheless, included in Debian so presumably
>> they are DFSG-friendly? The copyright file marks them as "UNKNOWN"
>> which is worrisome... I have found the following results about them:
>>
>> * [admon-warning.png][] seems to be [public domain according to this sketchy site][]
>> * [admon-note.png][] seems to have a [source in XFCE][], as part of
>>   the notes plugin
>> * [admon-tip.png][] is used in the Debian release notes, so is
>presumably fine as well [source there](https://www.debian.org/releases/testing/amd64/release-notes/images/note.png)
>> * [admon-important.png][], same, [important.png](https://www.debian.org/releases/testing/amd64/release-notes/images/important.png)
>> * [admon-caution.png][] can be found in Mediawiki as well, which is
>> a good source of icons. According to Debian, some are public domain,
>> some are LGPL (!?). In MediaWiki itself, the source of that file is
>> lost in the mists of time.
>>
>> Even though there is some confusion about the source of those
>> images, I think, in good faith, that they can be generally be
>> considered reusable. --[[anarcat]]

[public domain according to this sketchy site]: http://all-free-download.com/free-vector/download/tango_process_stop_115912.html
[source in XFCE]: http://git.xfce.org/panel-plugins/xfce4-notes-plugin/tree/data/icons/scalable/xfce4-notes-plugin.svg
[admon-warning.png]: https://moinmo.in/moin_static19/modernized/img/admon-warning.png
[admon-note.png]: https://moinmo.in/moin_static19/modernized/img/admon-note.png
[admon-tip.png]: https://moinmo.in/moin_static19/modernized/img/admon-tip.png
[admon-important.png]: https://moinmo.in/moin_static19/modernized/img/admon-important.png
[admon-caution.png]: https://moinmo.in/moin_static19/modernized/img/admon-caution.png

Update: I have made a [[plugins/contrib/admonition]] plugin for this
purpose, as a patch. Hopefully it will be mergeable here? Here's a
screenshot of what the help page would look like, to give you an idea
of the results:

<img src="http://paste.anarc.at/snaps/snap-2016.04.15-18.07.39.png" />

---

I like the idea of admonitions. I've done something vaguely similar on my own site ([e.g.](https://jmtd.net/film/blade_runner/)), but I just
use `\[[!template` and put up with the verbosity.I like that `\[[!tip` is shorter than `\[[!template id=…`. If
I was being a total purist I'd argue that the correct change would be to make a syntax shortcut
for the template syntax, since functionally that's what `tip` is doing, and include the
admonition styles in either `style.css` or in every shipped theme. But I'm more of a pragmatist
and your current plugin actually exists and IkiWiki is starving for contributors (IMHO)
so I encourage maintainers to merge it. I will probably merge it into [opinionated ikiwiki](https://jmtd.net/log/opinionated_ikiwiki/)
in either case (which will at least mean there'll be another avenue for people to check it out)  *— [[Jon]], 2020-08-07*

> One quick tip/request, [[anarcat]]: If you could update the "master" branch in your IkiWiki
> fork to match the merge base for your branches, it would be easy to use Gitlab's "compare"
> feature in-browser to see a combined diff of your changes.  *— [[Jon]], 2020-08-07*

> > Thanks for your support and comments! :) I don't have the time to manage another extra branch on top of the stack I already have unfortunately. but it might be simpler for me in the future... I keep on hoping all patches get merged and that i don't need to (more officially) fork `master`, but it seems that's where I need to go myself... In the meantime you can see the list of patches I maintain in [[users/anarcat]] and [my maintenance log](https://anarc.at/services/wiki/). I hope that helps! -- [[anarcat]]

> > Turns out I found the time. I merged all my active branches in the `master` branch on gitlab. not sure what you'd compare it against, but there, it's done. :) [[anarcat]]

>>> Thanks for that! I'll try to explain what I meant in terms of an example. your `admonitions` is  a series of commits that ultimately sit on top of
>>> upstream's `d0099568` ("Prepare release for unstable"). If I want to see a quick combined diff of all the changes made in that branch, I can try to
>>> use GitLab's "Compare" feature, but it does not let me specify a SHA to compare against, only a ref-name such as (your) `master`, which (at the time)
>>> was a much earlier commit than `d0099568`, so "Compare" would include all the unrelated upstream changes. If instead either `master` was `d0099568`, or
>>> `admonitions` was rebased on top of whatever your `master` was, then GitLab's "Compare" would be useful. As it is, I cloned locally and did the necessary
>>> `git` incantation. *— [[Jon]], 2020-08-12*

----

I've finally started playing around with this plugin. I think the default CSS needs
tweaking. I see "warning" has `padding` to try to account for the icon size, but 
the other admonitions do not. Perhaps they need to inherit some style from a common
class? Either way, the padding does not seem to work. This is a fresh ikiwiki with
the actiontab theme enabled:

<img src=https://jmtd.net/tmp/admonition.png alt="pic demoing admonitions" />
*— [[Jon]], 2021-02-15*