Multiline Placeholder Proposal#
I've added a link to MultilinePlaceholderProposal, which Gregor Hagedorn must have missed. The advantage of MultilinePlaceholderProposal is that it begins with a globally unique identifier (reversed domain name, like packages in Java).
--YvesPiguet, 27-Feb-26
Yes, I am new here, thanks! I am not sure why the multiline placeholder has to start on a new line prevents it from being usable in a large number of extension cases. I clarified that the Generic Extension Element may start anywhere, and may contain line breaks.
-- Gregor Hagedorn, 2007-02-27
Generic Extension Element Proposal#
I've been wanting to discuss this particular aspect of the proposal, just waited for the page to settle down. I believe that while we can suggest a plugin-naming scheme, the exact solution used is up to the wiki engine developer. It's very similar situation to how the page names in links and image names are treated -- the existing engines have such a wide range of working solutions that it would be impossible to come up with one that everyone agrees on.
Besides, the domain-like notiation is unnecessarily elaborate for something that is in common everyday use. It's ok for things like DTD that are usually copy-pasted or included in ready-made templates. It's ok for programming languages -- especially when you make some aliases to them anyways. But it'd be unacceptable to write about that <<unaffiliated.radomir.dopieralski.macro.latex source="$x_2$">> symbol as referenced in <<unaffiliated.radomir.dopieralski.macro.latex source="$x_2+y=c$">> formula using these elaborate names.
I say that leaving the plugin-naming conventions to the wiki engine has even more sense that for page names and images -- because these extensions cannot be moved between wikis anyways, so we really don't need any interoperability inside the box.
-- RadomirDopieralski, 2007-02-26
I think I would like to see this expanded alittle to optionally allow alternative content. Which would serve two purposes.
- When wiki engine doesn't know a plugin it can use the alternative. Like HTML's object element.
- Plain text markup can still make sense.
As for naming, I do think the dotted form is excessive. And certainly wouldn't want the plugging name embeddeded directly in the wiki markup. If I wrote a different latex plugin with the same interface as unaffiliated.radomir.dopieralski.macro.latex, I won't want to have to change the markup.
-- JaredWilliams, 2007-02-26
You have the choice between possible name clashes which must be handled in an ad hoc fashion, or some unique identifier. With unique identifiers, you can have a central repository, which is painful to manage, or a way to delegate naming to multiple people like with my proposition, with slightly longer names (of course nobody would ever choose something like unaffiliated.radomir.dopieralski.macro.latex). If you accept name clashes, it isn't worth having it in the standard, and it isn't worth having alternative contents because you can't be sure you won't map to your plugin something else with the same name.
To please everybody, I'd suggest that names with dots be reserved for reversed domains for people who care about the issue, but by experience, I feel it's a loosing battle.
-- YvesPiguet, 2007-02-27
The canonical domain name for my university's faculty is wmid.amu.edu.pl. This is actually very short, as we use acronyms both for the unversity and the faculty name. Other universities/faculties domain names tend to be longer. A lot of development happens on universities: you'd then have pl.edu.amu.wmid.macro.latex (the "macro" keyword is needed to distinguish it from similar plugins, like parser.latex, colorizer.latex or import.latex).
I agree about the choice between possible clashes and nice and clean namespace, and also about the benefits that allow you to make central repositories, indexing, put important documentation online, etc. But I believe that the choice is not ours to make -- it's up to the developer.
If you want to start standarizing the extension names themselves, you open a Pandora box of internationalisation and localisation. On a Polish-only wiki, I will naturally want to use polish names for plugins. But domain names don't allow (by default) the use of characters like ą or ę. I believe that Chinese users would have even more trouble.
I like the idea of an "alt text", I think the same syntax that is used for images, <<plugin paramaters|alt text>> would be apropriate? Of course, the alt text would be probably somehow distinguished from the normal text (tinted background? red text? frame around it?). I wonder what should be rendered when the plugin is missing and there is no alt text specified -- displaying the parameters might be too much (although they would usually give some hint on the intended contents), maybe just the name of the missing plugin?
Yves, I don't quite understand this sentence:
If you accept name clashes, it isn't worth having it in the standard, and it isn't worth having alternative contents because you can't be sure you won't map to your plugin something else with the same name.
Can you please elaborate?
-- RadomirDopieralski, 2007-02-27
It's worth having a standard for alternative contents only if there are cases where they'll be used, i.e. if Creole markup is rendered by an engine which doesn't have the extension. How can an engine know it doesn't have the extension if it can't be sure about the name?
- It doesn't have any extension. Ok, that may happen.
- There are local conventions for that particular wiki and pages written for it remain there. But then there can be local conventions for extension syntax, no need to have a standard.
- There could be some inter-wiki transfer, or pages which are published simultaneously on multiple wikis. Then there could be name clashes (for instance, many wiki engine developers will want a LaTeX plugin if it isn't supported at a more integrated level, so you'll have <<latex src="$a+1$>> , while others might prefer <<latex a+15>>. If you have alternative contents, how is it going
(BTW, when do we accept multiline list items? I'm used to multiline paragraphs because it's easier to read and it's supported by Creole; but if you look at the source code of this very contribution, you'll see that my three list items look weird, because I had to remove line breaks to let wikicreole scan them correctly.)
-- YvesPiguet, 2007-02-27
I don't think name clashes are an issue, since they're internal to the wiki anyway - it might even make sense to use something like <<plugin 1>>. If you want to have a global namespace for these, you will also probably need to add things like version information as well, and then it gets messy.
The whole point of the "plugin" syntax is that it allows a wiki engine to use native extensions without losing them in the edit. I don't think the point of actually *moving* content from one wiki to another has ever really been their objective.
-- Janne Jalkanen
I fail to see how using a domain name prevents name clashes when moving between different wikis. After all it's pretty common that someone makes a neat plugin and then makes several versions for different wiki engines.
I think that the content of <<...>> should always be considered engine-specific and either escaped or converted when moving between wikis.
You are right about the pipe. What other solution there is? "->" maybe? Or maybe if we chnaged th order of the alt text and plugin: <<this is some plugin|pluginname some|paramaters|with pipes>>...
-- RadomirDopieralski, 2007-02-27
Wiki A has 'latex' mapped to 'unaffiliated.radomir.dopieralski.macro.latex'. So <<latex src="$a+1$>> does its thing. Wiki B has latex mapped to 'unaffiliated.jared.williams.macro.latex' and uses <<latex a+15>>. Both can import the others pages, as long as they know how each other maps the markup to actual plugin implementations.
There is also the question of how much markup to allow in the alt text, allowing all the markup would allow better approximation of the plugins output. Could also allow plugin nesting, so if the outermost fails, it attempt a fallback to the next innermost.
I think there are few situations when the alt text would be displayed
When
- the plugin is missing.
- the plugin fails due to some exceptional circumstance (ran out of file space for instance)
If the plugin is missing or fails, and is going to degrade the quality of outputted page, then there should be some distinction, maybe a red bar to the left, with link to a footnote explaining more.
In PHP there is an error/warning message supression operator, @
So whilst Plugin insertion failed: Could not find plugin latexPlugin insertion failed: Could not find plugin latex would generate a warning around the alt text, Plugin insertion failed: Could not find plugin latexPlugin insertion failed: Could not find plugin latex still would use the alt text, but it wouldn't be highlighted. A plugin having no output, cant impact quality so using no alt and @ would be silently ignored as far as the user is concerned.
-- JaredWilliams, 2007-02-27
From Gregor, originator of this proposal:
I think the debate whether plugins are uniquely identied by Java conventions is, ok, but its importance would be where two wiki engines do want to be interoperable or achieve automatic translation.
The point of an extension element is that Creole does not know or cares what is inside, except that the end-of-extension-box marker is not inside. The point is that providing an extension box stops screwing the rest of the content (especially by wiki-specific escaping requirements), and thus simplifies porting of content.
First as an aside: The extension box that I envision is not limited to plugins in a narrower sense, i.e. generating dynamic content. For example, I find JSPWikis abilitity to support custom CSS styles on Wiki text quite useful (much better than dozens of #red# etc. special markup) and would envision that inside an extension box as well. Or features like "invisible comments", etc. that some wikis support.
For dynamic plugins, I do like the idea of optionally supporting an "alt-text" or "cached-result" very much. It would be relevant for Creole to anticipate it, because Wiki-editor software may need to know about it.
<<extension|cached-result>>
introduces the small problem that the bar character may longer be part of the plugin. I would favor:
<<extension>>|<<optional cached-result>>
That is, multiple extension boxes separated by a bar without any other blanks refer to the first one, the second optionally containing a cached html-formatted result
The cached-result is automatically generated, so ease of typing is no concern here.
With regard to the discussion about URL/GUID plugin identifiers, what about:
<<extension>>|<<optional cached-result>>|<<optional url-based plugin identifier>>
Perhaps that would simplify the migration, and would be added where confusion may arise, but not required.
-- Gregor Hagedorn, 2007-02-27
I generally like this proposal, but have one problem with it. This markup is not NonDestructive -- that is, if something goes wrong (for instance, an user forgets to close it) it will "eat" a large chunk of the page, making it disappear without a trace.
Most of Creole's markup is confined to a single paragraph and displays the text that is inside. This markup has neither of the two "safety guards".
Is there a way this could be made "safer"?
-- Radomir Dopieralski, 2007-Mar-24
Good point, I had never thought about this. However, any feature desiring to support hidden editing comments as part of this (a common extension of wikis) would have this problem.
Would a clarification help, that
a) the extension element may not be nested (i.e. not only the closing ">>>" but aalso the opening "<<<" are illegal content of the element.
b) the element must be closed on a page. It should be rendered literally, with an error message added at the start of the element.
-- Gregor Hagedorn, 2007-03-27
I'm not a fan of error messages, especially in things like markup. You're likely to miss them and they usually are not even in your language. Besides, nobody but developers reads them -- they are scary.
I'm rather thinking of something less dramatic, like rendering the thing as a pre block if anything is wrong (bad opening/closing, nonexisting plugin, error returned by the plugin) -- it might be a differently colored pre block if you insist on marking errors. Actually, you could even highlight the offending fragment. It's still error, though.
I'm wondering if splitting it to inline and block elements would improve the situation? You could limit the inline one to the end of paragraph then... but then empty lines would be forbidden too. Maybe the solution you propose is enough?
Can we have some example use cases for this? I'm probably exaggerating the problem.
-- Radomir Dopieralski, 2007-Mar-27
I agree with the idea of suggesting to implementers to render the whole block following an erroneous extension element start as pre if extension elements markup is incomplete. I personally do like simple, non-programmer-oriented error messages. The kind of error message I imagine is: "(Start of extension-element markup found; please end-markup of nesting another extension element!)" in red.
For example, the JSPWiki we work on will highlight errors in interwiki links and I find that quite helpful: JSPWiki:Main
is ok, No InterWiki reference defined in properties for Wiki called "JPSWiki"! is not. (as you see, JSPWiki could do better, by repeating the offending interwiki link, rather than replacing it with an error message...)
-- Gregor Hagedorn, 2007-03-28
Syntax: How about using a simplified version of LaTeX? I'm mixing this kind of syntax with Creole in my wiki and it works really well. Advantages: It's established, many people know how to read and write it.
\noargs
\command{arg1}{arg2}
\cmd[opt1=value1, opt2=value2]
\cmd[opt1=value1]{arg1}
\begin{environment}
\end{environment}
BTW: The way I currently parse my hybrid syntax is that the braces are dominant and inside a brace (as well as at the top level) you can have line-based Creole syntax.
-- Axel Rauschmayer, 2007-04-11
Axel, I don't quite understand, how do you want to mix it? Personally to me LaTex is a complicated markup language which I don't understand. I understand CSS, so for unlimited formatting, CSS would be my choice. Very personal and no poll! I am not opposed to making sure that a wiki could be in a mixed LaTex mode; that will certainly be very useful. But how do you achieve that? Do you propose to make single backslash a reserved Creole character? How is the end of the LaTex inline span defined? A new-line-character?
-- Gregor Hagedorn, 2007-04-11