# Extension Syntax

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This page is used to discuss and vote on a syntax for extensions to the MediaWiki software. These include:

• LaTeX (mathematics, formulas, chess..)
• musical notes (Lilypond)
• plots and timelines (gnuplot, ploticus, EasyTimeline)
• SVG->PNG rendering
• hieroglyphs (WikiHiero)
• map rendering
• 3d models rendering

¥ There will be a brainstorming phase of 7 days, after which voting will start on the proposals . The voting phase will last seven days.

Please read the arguments for and against below, add look at the concrete /Examples of each, before /Voting for or against on any you feel strongly about. Note that only registered users can vote.

(note also that some elements of the vote are still under discussion)

# Issues

• Find an easy to use and intuitive syntax
• Be consistent with already used syntax
• Be able to use data between the tag or from on other page
• If possible, don't forbid to use special caracters as data (ie. {{tag:data}} may forbid to use }} as data)

# Proposals

## MrMambo's proposal

It would be nice to add an interactive graph display for both mathematical functions and curves as well as the display of 2d projections of simple 3d - objects such as geometrical primiteves ( like the very useful cones / for cone sections) Proposed features:

• setting size of display in pixels
• setting unit scale in x and y direction
• inputting arrays of known functions of type f(x), f(x,y) and f(x,y,z), points, line-segments(edges), parametric curves, point-paths, bezier curves on the graph display
• setting display presicion (minum distance between each step on the curve / number of increments between two values etc.
• zooming in/out
• panning
• grid on/off + gridspacing
• display of crossingpoints between curves and solution of solvable functions.
• optionally adding a panel with sliders to control a set of variables used in the functions, curves, or other objects in the graph display.

I know this would be difficult to achieve. But one could start with the more basic features and expand it. I think one can realize this by using Action Script 2.0 for flash. Wich support external plain text classes (*.as) and reading from external text files.

MrMambo 13:18, 15 Apr 2004 (UTC)

## Erik's proposal

See examples...

We should use an XML-like syntax for extensions:

1. $insert code here$
2. <music>insert code here</music>
3. <hiero>insert code here</hiero>
4. ...

Long code segments could be moved into the template namespace and transcluded in the standard manner, e.g. [[Template:Beethoven's 9th Symphony (sample)]] would contain the <music>...</music> code, and could be transcluded using {{Beethoven's 9th Symphony (sample)}}. (This syntax obsoletes the current "msg:" syntax and will go live with the next software update.)

Arguments for:

• Many people are already familiar with XML-style syntax
• Indeed, many people are already familiar with using , and many articles already include this syntax.
• It is immediately obvious over long segments of code what class a particular segment belongs to (i.e. you can look at the bottom of a music segment and know that it is music code, because there's a </music> closing tag)
• It is easy to remember (at least for HTML-savvy people)
• It is sufficiently unique to avoid parsing problems (as opposed to a short sequence of control characters, which might conflict with any present or future extensions)
• It is easy to standardize the parser for it
• It is at least somewhat more wiki-like than "<rend class="music">"
• It is consistent with existing uses of different kinds of brackets
• [ is associated with links ([ext. link] [[int. link]]); { is associated with "transclusion" (e.g. {{NUMBEROFARTICLES}}, {{msg:foo}} and the up-coming {{foo|bar=baz}} templates); < is already associated with HTML and HTML-style formatting tags (such as <sub>, <small>, <pre>, <code>, <nowiki>...). The extension syntax is marking a special formatting rule for the enclosed text, and therefore fits with the other uses of <foo></foo>.

Arguments against:

• In short segments of code the redundant closing tag can be annoying
• Needs to be localized
• Easy using Tim's MagicWord class, which also allows for synonyms, e.g. the English version could be valid in all translations to allow for easy copy & pasting. Possible disadvantage of confusing users ("what's the difference between "math" and "qxyz"?), but most users who would deal with these issues would probably be familiar with both languages.
• Gives the false impression of being real HTML or XHTML
• arguably, it is real XML
• I rather dislike the asociation that it's XML. We should think of it as an arbitrary syntax convention styled after XML, because otherwise we'll start thinking of it as a hierarchical element structure, which is not the case with wiki-markup in general. (In the same way, Lilypond's authors stress that it's not TeX, even though it looks similar) - IMSoP 16:38, 31 Mar 2004 (UTC)
• In turn gives (to the slightly less technically- and logically-minded people) the false impression that Wikipedia allows all of HTML
• Less technically and logically minded people probably don't know what HTML is anyway, and those who do will easily figure out what works and what doesn't
• Gives the false impression of nestability ($x^2 = <hiero> b </hiero>$)
• The nesting argument can be applied to any syntax that has different opening and closing tags. Nestings will be possible where they make sense, just like you used the <nowiki> tag to create the example above, a case of nesting. Nestings are not possible / have no effect in HTML where they do not make sense.
• Rather hard to type
• Easy to go wrong and mess up a whole page ($x^2 [itex]) • We could auto-fix that • that could begin to make the parser's behaviour more confusing and less predictable • Hardly, as it would only happen during errors. There is no slippery slope here. • Generally just as easy to spot and fix • The same is true of <nowiki> or <pre> or any of the other HTML/XML-like tags we already use • then this is equally an argument against <nowiki> and <pre> • Goes counter to the trend of instituting a wiki-like syntax for everything (like tables); if tags-that-look-like-HTML were what we are looking for, we wouldn't have needed the wiki table syntax. • The reason we created a table syntax is that tables consist of many, many different, nested tags. • articles with a lot of mathematics and chemistry would then also contain many, many tags. • Identical and in clear distance from another, not nested and different. • This syntax will only create the same number of tags as any other syntax on this page. The only difference will be the form (including size) of those tags. • There is no real trend to replace "everything" with our own syntax (e.g. HTML table parameters, CSS and DIV tags). • Difficult to read, because the tags distract and don't give an intuitive visual appearance of encapsulation (parenthesisation, or whatever you call it) • Among programmers/hackers/geeks, the tags are the most widely recognized form of labeled encapsulation. Laymen, however, may find it hard to grasp. • Lay people managed to grasp WordStar and WordPerfect, both of which use text within tags for formatting. • Unlabeled encapsulation is confusing over large segments, and more difficult to learn because the brain recognizes and remembers new words easier than new symbols • <> and </> are no less symbols than [[ and ]] are (i.e. this is not the only form of labelled encapsulation suggested here) • Nobody claimed it was. It is, however, the most widely recognized one. • New extensions could potentially clash with other kinds of markup which use the same syntax (though unlikely) ## Magnus' proposal See examples... For images: [[image:xyz.svg]] can produce a PNG or an SVG, depending on user settings or browser identification. That can utilize goodies like thumbnail generation etc. An image is an image is an image, after all. For more complex structures (hiero, music): {{music:stuff}} or {{music::stuff}}. The first variant will use "stuff" directly as data, while the second one will use the data stored in [[stuff]]. That way, a complicated timeline can get its own "article" (I suggest a "data:" namespace), while a few hieroglyphs can be entered directly. Alternative for page reference (result of discussion): • {{music:[stuff]}} • {{music->stuff}} Pros : • Simple syntax • Consistent with existing syntax • {{}} parser is already in place • Allows for easy handling of large amounts of raw data without cluttering the article source • Easy to type Cons : • Needs to be localized (easy using Tim's MagicWord class, which also allows for synonyms, e.g. the English version could be valid in all translations to allow for easy copy & pasting) • Re: images, does not allow for SVG editing as specified • Re: extensions, makes large blocks of text difficult to read because it's not clear what the closing tag refers to (as opposed to, e.g.$, where it is immediately clear that it ends a math block
• And if we need }} in markup ? Regular expression to match {{.*}} is not a "parser". Taw 18:50, 28 Mar 2004 (UTC)
Why not? I fail to see the problem here. If you want to display two curly braces in the text, put them in <nowiki> tags. -- Stw 10:45, 29 Mar 2004 (UTC)
2 curly braces in embedded markup, not in text: ${\displaystyle {\frac {10^{15}}{\pi }}}$ (\frac{10^{15}}{\pi}). That's very common combination in TeX. One of the reasons why I chose  was because there's no chance in hell that [/itex] would appear in math markup. Taw 01:56, 30 Mar 2004 (UTC)
• The brace syntax currently in CVS removes the need for an msg: prefix when including templates. Thus, prefixes such as music: and hiero: would compete with namespaces, pseudo-namespaces, and several other recently-added special prefixes including ns:, localurl: and localurle:
• functionally non equivalent to {{ }}: msg inserts a static template (like a macro) while extension creates (and inserts) new content (without having a related [template] page). the "->" format, however, looks different enough.

I'd like to see the extension part go away in image links. The link should be [[image:xyz]] so that whatever format happens to be best can be used. Currently one can't change the format of an image without uploading to a new name (with the new extension) and then changing all the links. Replacement of an image could be done with a special 'replace image' link on each image page. Audin 04:07, 30 Mar 2004 (UTC)

## HTML like (with same end marker)

See examples... alway same end marker

$...<end> <music>...<end> <hiero>...<end> pros: cons: • confusing for those familiar with HTML/XML-style syntax, who will expect the$ style ending.

## Forum like (with no /) (Aoineko)

See examples...

[math]...[math]
[hiero]...[hiero]
[music]...[music]

## Forum like (with same end marker) (Aoineko)

See examples...

[math]...[end]
[hiero]...[end]
[music]...[end]

## Magnus' proposal alternative 2 (Aoineko)

See examples...

{{math:foo}}
{{hiero:foo}}
{{music:foo}}

Where the software check if foo is a valid page (data:foo). If true, parse the data page; If not, parse the text in tags.

## Uli's Proposal

See examples...

Abstract: This is essentially a variant of Erik's proposal with more intelligent templates.

I had suggested a thing like that some time ago in the discussion on navigation bars. As I understand, we have some issues, that should be covered:

• Navigational data (like theme-rings, article grouping ("history of germany, part 1..)) which should not be rendered at the position they are placed in the text, but instead at a - probably skin specific - position, and possibly only in certain situations (for example, theme rings should not be rendered in a print view).
• Defining short non-textual data within articles (Hieroglyphs), to be rendered at the position where they are placed
• Including long non-textual data, to be rendered at the position where they are placed
• Possibly also including long non-textual data, to be rendered at a specific position (I'm thinking at those large information tables in the upper right corner of states, cities, elements and so on)
• Probably we want to have some sort of parameters to pass to a transcluded item

So, suppose we get a namespace "Include:". We would seperate that namespace again by convention into type-specific segments, so article fragments containing music data would to be named "Include:Music:Beethovens 9th Symphony", Tabluar data to be included into an article would be named "Include:Table:Dollar rate since 1991", the big tables (upper right corner) possibly "Include:Infotable:Uranium", a navigation bar "Include:Navlist:10 largest cities of Island" and so on. It's important to have the type of the included data somehow coded into the article name, so you can render that fragment stand-alone!

Those fragments would be included with the already disussed syntax {{Music:Beethovens 9th Symphony}}, {{Infotable:Uranium}}. For not-included data, I'd prefere the XML-type syntax () - transcluding is something different than switching the syntax within the article, so we should seperate those two use-cases.

Very important: depending on the type (Music, Infotable, Navigation, ) of a transcluded fragment the software should not only decide on how to interpret the given data, but also on when and where to render.

## Peter's proposal

See examples...

<rend type="math">...</rend>
<rend type="hiero">...</rend>
<rend type="music">...</rend>

pros:

cons:

• complex syntax, which is more suitable for programmers than users

## Inline brackets proposal

See examples...

[!math x^2 + y^2 = z^2 !]
[!hiero b-l:a-h !]
[!music do re mi fa sol !]

Pros:

• Easy to type

Cons:

• Isn't really consistent with existing syntax

## Symbol bracket proposal

See examples...

 [[! x^2 + y^2 = z^2 !]] (for math) [[^ b-l:a-h ^]] (for hiero) [[# do re mi fa sol #]] (for music)

pros:

• no key word to translate
• quick to type
• not significantly more difficult, for some perhaps even easier, to remember than "<someword> ... </someword>"
• easy to read in source text, provides visual encapsulation/parenthesisation
• easy to get right (it is intuitive to think you have to close the brackets you open)

cons:

• Looks like a link, but isnt
• Not an argument — nor is [[Image:]]. — Timwi 13:44, 30 Mar 2004 (UTC)
• Well, in a sense it is: it links to an image somewhere else. Formulae don't involve anything stored anywhere else. IMSoP 00:50, 31 Mar 2004 (UTC)
• ... yes they do ;-) But I see your point. — Timwi 10:04, 31 Mar 2004 (UTC)
• not obvious which markup refers to which feature
• hard to memorize or even only to recognize - with more and more randomly assigned special characters we might end up with a syntax that is only comprehensible for Perl programmers Erik Zachte 00:52, 31 Mar 2004 (UTC)