Talk:XML

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[edit]  %28 replaces ascii '(' ??

What do they call this ascii replacement scheema you see it often in xml pages and url links? —Preceding unsigned comment added by 75.69.135.171 (talk) 02:06, 10 January 2008 (UTC)

see: http://www.w3.org/International/O-URL-code.html DRead (talk) 23:34, 23 May 2008 (UTC)

[edit] Advantages/Disadvantages

The Advantages/Disadvantages in the "Critique" section could be organized better, I believe. Instead of having separate "advantages" and "disadvantages" sections, I think it would be better if the advantages and disadvantages were interleaved so that related points could be together. For example, there are a couple of pros and cons related to it being text-based. There are also a couple of pros and cons related to the data model.

Another problem with that section is that an advantage/disadvantage needs a point of reference. For example, "it is text-based" is not an advantage over other text-based formats. Each pro/con should be something like "it is XXX, while formats like X, Y, and Z are not".

The Advantage/Disadvantage section is segmented the way it is because all alternate attempts at structure have proven entirely inappropriate. For example, the previous formatting of this section consisted of entirely unreferenced and self-contradictory "back and forth" with one sentence by a proponent, quickly followed by a sentence tacked on later by an opponent, subsequently followed by a cutting retort from yet another proponent -- each person adding in content without regard to the merits of the "opposing view" ... and without regard to whether their points had already been made by someone else already.

The result was a mish-mash of contradictory and irrelevant Non sequitur that was simply unreadable -- and almost all of it was unsupported by cites. The current section represents a compromise to lift the article out of that unmaintainable morass. dr.ef.tymac (talk) 23:34, 24 December 2007 (UTC)

[edit] Populating an xml database

I have seen several basic XML tutorials and they talk about creating an XML database by typing lines such as:

 <name>John</name>
 <age>34</age>

etc. etc That's understood. But,

what if I have a comma or tab separated text file of 1000's of names? Surely I do not have to write:

<name></name>

1000's of times?

So how do I import the data from a text file?

???? —The preceding unsigned comment was added by Pokerscouse (talk • contribs) 16:02, 3 January 2007 (UTC).

You write some code that loops through the lines of data in your CSV file, and outputs the correct XML for each item. There would be a neat way to do this in just about any current programming or scripting language. Maybe, if you're less technical, you could import it into a spreadsheet, then export the spreadsheet as something like HTML, but you'd have little real control over the XML element names etc. --Nigelj 20:10, 22 January 2007 (UTC)

[edit] Can anyone answer this re xml?

I am studying XML. I find that some of the commands in the tutorial I am using, do not produce brower display results that the author says they should, particularly when the @ symbol is used. I only have IE 5.5 and cannot upgrade to 6.0 because that is not possible without an internet connection, which I do not have in my dingy flat. Is I.E. 5.5 the cause? —The preceding unsigned comment was added by Pokerscouse (talk • contribs) 15:06, 6 January 2007 (UTC).

This talk page is here to discuss improvements to the article on XML. It is not a place to get help or assistance on usage of XML, and I suggest you look for one of the many forums, having XML/Web technologies as topics, available on the net in order to seek answers to your questions. Jerazol 15:17, 6 January 2007 (UTC)

[edit] Empty elements in XHTML

I removed the following line from section XML#Empty elements:

Note that they may, however, be treated differently if they were examples from XHTML that was intended for processing by various current and historical web browsers.

The above sentence flasely suggests XHTML treats <foo></foo> differently than <foo/>. It's true that historical browsers will choke on the abbreviated form, but so what? Old browsers choke on CDATA sections as well. —Ryan 10:02, 11 January 2007 (UTC)

Actually, this is true for "modern" browsers like Firefox and IE 6 as well. For instance, the <script> or <textarea> element, to mention some, cannot be written as empty elements. This is though, irellevant, imo. Since this is an article on XML I don't find it appropriate to mention special case applications deviating from the XML-standard. Jerazol 10:38, 11 January 2007 (UTC)

[edit] Extended to?

Hi, I'd like to draw attention to the list of "Extended to" in the infobox, which currently lists lists "XHTML, RSS, Atom, ...". XHTML is an application of XML rather than an extension of XML, and I think these values would be better against the "container for =" parameter. This can be seen by the requirement that all XML document formats start with an XML preamble, similar to TIFF having headers which allow sub-formats within them.

I doubt there are any clear cases of extensions of XML, but if I had to nominate one, it would be RDF.

Likewise, I think the XHTML page should be changed from "Extended from: XML, HTML" to "Contained by: XML; Extended from: HTML". John Vandenberg 07:38, 23 January 2007 (UTC)

XHTML is a subset of the XML language. XHTML documents are also valid XML documents. RSS documents are also valid XML documents. I prefer to call these XML "dialects," as they more accurately describe what the languages actually are in relation to the base language. —Preceding unsigned comment added by Dgmjr05 (talk • contribs) 00:11, 28 April 2008 (UTC)

[edit] WML

I apologize if you do not want this here, but I invite all that have XML knowledge to participate in the WML group.-- Nirelan

[edit] Arcane ideas such as nillability

Database-related data transfer has been supported with arcane ideas such as nillability. I can't find any supporting information as to why nillability (ie. nullability?) is arcane (or why people think it is). Christiancatchpole 00:35, 12 February 2007 (UTC)

[edit] External Links

How are these EXTERNAL links, may I ask?

• Expat free software stream-oriented XML 1.0 parser library, written in C.
• Libxml2 free software XML C parser and toolkit.

Nousernamesleft 19:05, 17 March 2007 (UTC)

[edit] Free vs Free software

Imo, it doesn't really make any sense to write "free software" in this context: http://en.wikipedia.org/w/index.php?title=XML&diff=116854292&oldid=116845869

The reason why I reverted it the first time round, was that I read the diff wrong, thinking that he had added "software", not removed it. If you want to use "free software" instead of just "free", the sentances should probably be rewritten. Jerazol 20:10, 21 March 2007 (UTC)

[edit] Game Mods

In some games, XML files are used as mods, there should be something on that. 72.130.236.182 19:12, 27 March 2007 (UTC)

Not really. Remember; XML is a general markup form and can have a wide variety of applications. This does not warrant inclusion just because some games utilise XML for mods. Said games can use INI, SQL, etc. Sicanjal 12:57, 19 April 2007 (UTC)

[edit] Bullet List in Criticism Section has too much debate in it

I was looking for the pros and cons of xml and in the criticisms section, almost every bullet item had with the criticism a rebuttal (withing the bulleted section). A couple even looked to have a rebuttal to the rebuttal. A bulleted list by its nature is intended to transmit clear and concise/short points. Adding rebuttals into the bulleted text and turning each point into a debate runs counter to that and makes the section less clear. I suggest it would be better to clean up the section and give each criticism its own point. Should someone want to rebut them they could do it in a short summary below the bullet list. After all, the section is titled 'criticisms', not 'debates'. You may disagree with them, but a point wouldn't still be there if enough people disagreed with it (i.e. there must be more than a few people who have the same criticism). Let the point be made clearly and debate it elsewhere. Theshowmecanuck 23:11, 27 March 2007 (UTC)

Yup. The problem is not likely to go away, however, since there is doubtless a substantial number of contributors to this article who do not believe "XML cricitisms" of any sort are valid to begin with. Notice how pristine and concise the "Strengths" section is compared to the "Criticisms" section? You are free to clean up the section yourself, but just be ready to defend your actions. (See also Holy_War). dr.ef.tymac 23:55, 27 March 2007 (UTC)

I've made some substantial editing to this section, and I'm sure several will disagree with my edits. I think having a discussion on weather a criticism is valid or not in the article is nonsense, so let's try to agree on which criticisms can be seen as valid and get reasonable sources for these criticisms. Jerazol 08:02, 28 March 2007 (UTC)

Although your "scortched earth" approach to editing may be a matter of some concern, I agree in principle with your efforts. I also agree with your point on "validity" ... a comment regarding cites is (I think) appropriate here. dr.ef.tymac 20:08, 28 March 2007 (UTC)

Follow-up: I've added cites and given some attention to the "criticisms" section. That's all I have energy for (for now) but there is still some removed "discussion board" content that may be worth re-adding (at least as qualifying footnotes). Also there are probably some typos to be cleaned up. dr.ef.tymac 21:32, 28 March 2007 (UTC)

The section: "criticisms" really should be changed to "weaknesses", and remove some of the citations. There are no citations for the Strengths, and some of them are questionable (e.g. XML is usually not human-readable in practice). Come on, the weaknesses of XML are pretty obvious, just as some of the strengths are. --The_Riddler 07:48, 29 March 2007 (UTC)

1) change "criticisms" to "weaknesses": Disagree. If you read the cited materials, you will notice not every criticism is characterized as a "flaw" with XML itself. Some simply say XML is not the right tool for every job. Do you say it is a "weakness" that a hammer is not a drill?

2) remove citations: Disagree. The opposite is actually appropriate, every item not yet cited in that section should be cited. We've already seen it devolve into a debate forum, requiring cites is a reasonable measure to combat that tendency. Grab some reliable sources and start helping out by adding cites.

3) general problems with wording: Agree. I do think you indirectly identified a different problem, the term "strengths" is not really appopriate either, no more than "weaknesses" I will address this. dr.ef.tymac 14:00, 29 March 2007 (UTC)

4) change "criticisms" to "weaknesses": Disagree. It seems to be a fairly standard section heading for quite a large number of articles in the Wikipedia. Especially those relating to programming and programming languages. It doesn't make sense to rename it for this article. —The preceding unsigned comment was added by Theshowmecanuck (talk • contribs) 20:30, 7 April 2007 (UTC).

Added infos to alleviate two of the criticisms : higher storage transmission and processing costs (cf. Binary XML); and no intrisics data types (cf. XML schema). Hervegirod 11:43, 1 April 2007 (UTC)

Kept the infos, but moved them to footnotes. People who are interested in the nuances can look there, and the bulleted lists still remain uncluttered, which was the original rationale for the recent major change to begin with. dr.ef.tymac 16:34, 1 April 2007 (UTC)

Good idea, I agree with that ! Hervegirod 20:17, 1 April 2007 (UTC)

[edit] Wrong statement about comments

I deleted the following text:

 <!--Invalid comment-->

I can't find anything in the spec which supports this proposition. --Cameltrader 21:44, 13 April 2007 (UTC)

[edit] Page for various XML schemas?

As the top of this article says, there are thousands of XML-based application languages (MathML, RSS, SVG, DocBook, ChemML, etc). Is there a wiki page which lists all of these? I could not find such a page, but it would be very useful to many, I'm sure. JECompton 02:27, 15 April 2007 (UTC)

Just go to Category:XML-based_standards. The XML article category itself is huge and sorely in need of organization. Nevertheless, you won't have trouble finding loads of information if you are willing to hunt and click. dr.ef.tymac 02:41, 15 April 2007 (UTC)

Thanks very much. Even in its unorganized state, it is helpful to me at least as a listing of some specs out there.JECompton 02:45, 15 April 2007 (UTC)

I added some short explanations on the article List of XML markup languages (no more than one sentence, just to present each language). It is not finished yet, but I thought it could be useful. Hervegirod 09:01, 15 April 2007 (UTC)

[edit] Not a markup language

The first sentence of a wiki article is the most important, and I find "The Extensible Markup Language (XML) is a general-purpose markup language." likely to perpetuate ideas about XML being a "new" version of HTML. XML is not a markup language. I would prefer it described as either a spec to define markup languages or a metalanguage.139.133.7.37 19:49, 17 April 2007 (UTC)

Request: Propose wording that you think corrects this problem, and then post it here on the discussion page. dr.ef.tymac 01:16, 18 April 2007 (UTC)

The Extensible Markup Language (XML) is a specification for creating custom markup languages. 139.133.7.37 20:43, 18 April 2007 (UTC)

Done. What I did was add your clarification to the lead as an internal cross-ref. The rationale is as follows:

• in general, you raise a valid point about the potentially misleading implication
• the official name "XML" is (let's face it) as much a marketing tactic as it is a descriptive name
• the point you raise is really a symptom of how the "marketing" collides with "technical accuracy" ... more people understand "markup language" than "lexical specification" or "meta-language"
• because the "ML" of the official name stands for "markup language" it would be potentially confusing to a general audience to imply it stands for "meta language"
• the technical accuracy of your point is preserved, but it is indicated in a footnote. This keeps the lead section concise, minimizes potential for confusion, while still including your clarification in the article.

This seems like a reasonable solution to the common problem of clarifying "introductory-level language" that is technically inaccurate, but nonetheless widespread. Hope that helps, comments and feedback of course welcome. dr.ef.tymac 21:09, 18 April 2007 (UTC)

Agree with all your points, and the solution139.133.7.37 15:57, 19 April 2007 (UTC)

I don't agree. It is more important to write things as correct as possible. Not as 'simple' (to most people) as possible. I suggest to switch the reference with the first line, so things would look something like this: The Extensible Markup Language is a general-purpose specification for creating custom markup languages. And the reference says something about the fact that it can be confusing (becaulse of the name XML etc). —Preceding unsigned comment added by 80.126.42.203 (talk) 09:21, 20 February 2008 (UTC)

*frustration* The article suggests in many ways that XML is a language. We should not write a simplified description of what XML is. This means: XML is -no- markup language, it has no file extension etc. Anything what makes people think that XML is something wich it is not, should be removed from the article. It should me much more -exact-. 80.126.42.203 (talk) 14:48, 2 March 2008 (UTC)

The 'L' of XML stands for *language*. This is what w3c define it as. It doesn't get clearer than that. But what makes a language? Via XSLT, XML has loops and tests. It's as much a language as AWK. It's a language even if it's not Turing complete.

What do you mean 'it doesn't have a file extension'? The XML page clearly shows it with the file extension of .xml. Not that having a file extension is a requirement of a programming language (see shell scripts). peterl (talk) 21:40, 2 March 2008 (UTC)

You have a good point questioning what a laguage exacly is. I don't know anything about XSLT/awk and not even much about XML. But I think that a "specification to create markup languages" a good description of XML. This also means it is not a language itself. With the file extension i mean: a file wich contains a markup language wich complies to the XML specification could have a file extension. Something like .xhtml. But a 'specification to write markup languages' is no file and has no file extension. 145.48.123.117 (talk) 14:54, 3 March 2008 (UTC)

Hmm, I might be wrong.. sorry.. 15:06, 3 March 2008 (UTC) —Preceding unsigned comment added by 145.48.123.117 (talk)

Sorry again for saying dumb things. I do still think that the '{{Infobox file format'-box should be removed. It's saying nonsense like 'Type of format: Markup Language' etc. XML is not a fileformat at all. —Preceding unsigned comment added by 80.126.42.203 (talk) 20:41, 7 March 2008 (UTC)

The note itself "It is often said to be a markup language itself. This is incorrect." in the references section requires some citation. It is no good to use the note/citation in the article without a citation to back it up, particularly as this is related to a major misconception. It may as well say "XML was invented by alien cows" otherwise. —Preceding unsigned comment added by 81.106.206.248 (talk) 20:58, 21 April 2008 (UTC)

[edit] Data or document oriented XML

I removed Tpox's contribution which was summarizing Bob DuCharme's "Documents vs. Data, Schemas vs. Schemas" conference paper. Although I agree that the article should mention what kind of information gets modeled in XML, DuCharme's assertion that XML documents are either data or document centric (but sometimes neither or both), seems to be primarily just his own observation that he makes for the purpose of providing possible criteria for the selection of a schema language. I don't see evidence that this is a meaningful distinction in general, even if it is one that some people do choose to make, especially since he admits that there are often exceptions. Likewise, it's not particularly noteworthy or crucial to the reader's understanding of XML. —mjb 09:39, 3 July 2007 (UTC)

[edit] Just passing through

I noticed under Well-formed and Valid XML Documents --> Well-formed documents, the statement "contents of this subsection should be absorbed above". True or not, this comment seemed more appropriate on the talk page than within the entry itself. I will remove it, but I leave the comment here for others to determine its validity. 65.56.85.32 20:31, 17 July 2007 (UTC)

[edit] Push vs. pull: clarification needed

An anonymous visitor rightly points out that Java STaX is a "pull" model, yet it is given as an example of "push" in the article. I don't think it's appropriate to blindly substitute "push" with "pull" in that section, though, since the Fitzgerald and Ducharme references apparently support the notion that it's push, not pull, that's gaining popularity. Can someone analyze this section and make it clear what's push and what's pull? —mjb 03:10, 3 August 2007 (UTC)

STaX is pull parsing, and this is the approach gaining popularity lately (although quite slowly). The discussion in this paragraph mixes arguments related to pull parsing (code easier to understand, allows to keep state in local variables) with background information on push parsing (most natural form using a recursive descent parser, well known in compiling theory). I think this section should be cut in two different sections, "Pull parsing" illustrated with SAX, and "Push parsing" illustrated with STaX and its ancestor XMLPull API. While "Pull parsing" is more friendly for the users of the parser, "Push parsing" is still the most popular option for implementor because it is much more straightforward to write a push parser starting from grammar productions. - 82.247.18.131 22:46, 12 September 2007 (UTC)

Although i'm also "just" an anonymous visitor im also wondering about stax inside of push?!Could u change this? I guess i come back and see in 2 months if it didn't change by then i try to change it then here :) —Preceding unsigned comment added by 164.61.216.36 (talk) 06:51, 26 September 2007 (UTC)

I've fixed this. That section was way off in multiple ways, and may still have more prominence than it deserves. I've also fixed several other issues in these sections where people seemed to be using Wikipedia to get attention for their pet XML projects that have not achieved broad adoption, support, or consensus within the community. 209.212.73.133 (talk) 17:31, 29 November 2007 (UTC)

The section still needs some clarification, especially regarding following assertion

This allows for writing of recursive-descent parsers in which the structure of the code performing the parsing mirrors the structure of the XML being parsed, (...)

which does not seem justified nor grounded on any reference. I do not think the reference to "recursive-descent parsers" really helps to make things clearer as it confuses two levels: the handling code is actually similar to recursive-descent parsers, but is not a parser per se, and the underlying XML Pull parser can be based on a recursive-descent parser or not. I propose to remove the mention of recursive-descent parser altogether and put something like:

The main difference between event-based parsing (or Push mode) and iterator-based parsing (or Pull mode) is the module which drives the flow of control: in Push mode, it is the XML parser, while in Pull mode, it is the handling code. The major impact is that the handling is more simple to write in Pull mode (while making the parser more complex) since keeping the flow of control also means keeping local variables alive. This allows intermediate parsing results to be stored and accessed as local variables within the handling methods driving the parsing. Examples of (...)

- Eric 213.128.113.197 (talk) 01:14, 7 February 2008 (UTC)

To complete my previous comment, it may be worth creating a separate subsection to introduce the two layers (XML Parser written by XML parser implementers and Handling code written by application developers). This may also be a good place to discuss comparison of XML with more general parsing theory and compiling. I'm not too proud of the term "Handling code" by the way so if anyone has something better to suggest... - Eric 213.128.113.197 (talk) 01:19, 7 February 2008 (UTC)

[edit] XML is not a true subset of SGML

The introduction should be claried. Though XML started as a subset of SGML, it is not a true subset as it adds features compared to SGML, and XML parsing incompatible with SGML (an SGML parser can not parse XML). Carewolf 12:01, 16 August 2007 (UTC) In fact with the SGML Web Annex, SGML was extended so that XML was (once again)a true subset. --Nantonos 20:34, 12 September 2007 (UTC)

[edit] Sources

In the section entitled "Sources", it says "XML is a profile of an ISO standard SGML". What does this mean? In particular, how is the word "profile" being used here? Does it mean "subset"? (but see the comment immediately above mine, entitled "XML is not a true subset of SGML"). Mcswell (talk) 05:59, 8 January 2008 (UTC)

I second this question and think it should be clarified. The article says XML is a profile, the XML specification says "XML is designed to be a subset of SGML", but the SGML article says XML is an application of SGML. Which is it? If XML is a subset of sgml but not necessarily an application does that mean it could be an application? --ott0

[edit] Need to define allowed syntax for tag names and other tokens

Like articles on programming languages, this article needs a definition of what constitues a legal name, tag, token etc. before it begins to discuss more advanced aspects of tree structures.

For example Can there be a space between the '<' and the beginning of a tag name? Is <9tagName> a legal tag?

[edit] EXI

The article needs to mention Efficient XML Interchange (EXI) http://www.w3.org/XML/EXI/ --Nantonos 20:33, 12 September 2007 (UTC)

This is correct! EXI will be THE binary standard, and it is convertable from/to XML without loss of information. —Preceding unsigned comment added by 80.141.92.250 (talk) 14:40, 21 December 2007 (UTC)

[edit] Some XML terms

I believe the main text needs a bit more beef, but I hesitate to add such content since it's a bit too much for most people... you can keywords search from inside Visual Studio 2005 if you have it. --Raylopez99 20:57, 1 October 2007 (UTC)

[edit] Neutral point of view?

The citation "XML is really just data dressed up as a hooker" should be removed. —Preceding unsigned comment added by 193.49.124.107 (talk) 12:26, 29 January 2008 (UTC)

[edit] icon

the icon/graphic for this article does not add anything and should be removed. —Preceding unsigned comment added by 74.202.89.125 (talk) 19:34, 4 February 2008 (UTC)

Although I agree the example could be made a little more neutral, I think it is quite representative of XML, being short and showing explicit syntax of elements, text and comments. It also shows how XML is different from HTML, by using markup not related to presentation. 213.128.113.197 (talk) 00:39, 7 February 2008 (UTC)

[edit] International use

I think this section would really deserve to be extended. I suggest putting more emphasis on the relationship with Unicode here. If someone has any details related to XML design with regards to Unicode from an historical point of view, it might be interesting. A discussion of XML adoption in different countries would be great too. - Eric 213.128.113.197 (talk) 01:29, 7 February 2008 (UTC)

[edit] Validation report on ISO/IEC 19503 ????

Would anyone please kindly provide me the citation of the validation report published in literatue??? Thanks —Preceding unsigned comment added by 64.62.138.94 (talk) 05:54, 24 February 2008 (UTC)

[edit] What XML is and Relation to SGML

I think that for the people who already have some knowledge of HTML that the fact XML cannot actually be "universally interpreted" beacause it is more of a pseudo language. And the fact it cannot "universally interpreted" the statement that it is "a simplified subset of SGML" is misleading and should be clarified.--Melab-1 (talk) 21:48, 24 April 2008 (UTC)

[edit] Not a language?

In the context of computational theory, XML is indeed a language. Ask any mathematician or computer scientist. It can be represented using standard grammars and (without actually doing the formal proof because I'm tired and don't feel like it) I'm pretty certain I could prove that RSS, XHTML, XSLT, etc. are proper subsets of XML.

Anyway, what is the rationale for representing it as a specification or file format rather than what it is? I read a couple of posts about people being confused that it is a subset or replacement for HTML or something like that. The community would be better served with an accurate depiction of the topic versus a not-so-accurate one. —Preceding unsigned comment added by Dgmjr05 (talk • contribs) 20:41, 25 April 2008 (UTC)

[edit] Well-formed examples incorrect

The section on well-formed documents includes examples that are incorrect, including this one:

<title>Book on Logic</title> <author>Aristotle</author> <title>Another Book on Logic</title> <author>Boole</author>

This is an incorrect example because the XML recommendation states that to be considered well-formed the XML must meet the definition of "document" as defined in the recommendation. "Well-formed" and "document" are defined here: 2.1 Well-Formed XML Documents

So, to truly be well-formed the example listed above must have a single containing element. In addition, to be truly meaningful, it would likely make sense to wrap each repeating sequence and call it what it is (a "book"). I would suggest the following makes the most sense:

<books> <book> <title>Book on Logic</title> <author>Aristotle</author> </book> <book> <title>Another Book on Logic</title> <author>Boole</author> </book> </books>

Thanks. I think I've clarified that now. TimR (talk) 09:51, 25 May 2008 (UTC)

[edit] Describing XML

Might XML best be described as a syntax, rather than a markup language? I suppose this could be considered similar to the way that Java, Perl, JavaScript, etc. are described as having a C-like syntax. Note: I am not advocating this label. The idea popped into my head, and I wanted to see if anyone else agreed. Yes, no, maybe? Karl Dickman ^talk 00:17, 30 May 2008 (UTC)

[edit] DTD / schema considered "semantic?"

Why do we use the phrase "semantic rules" to describe the DTD / Schema? These seem like syntax rules, not semantics to me. I think of syntax as describing the set of acceptable strings (documents) and semantics as describing the meaning or execution process.

KLuwak 02:42, 10 June 2008 (UTC)