# XML parser with file names and line numbers **URL:** \ **Category:** Ruby\ **Created:** [April 21, 2006, 12:01am UTC](https://www.ruby-forum.com/t/xml-parser-with-file-names-and-line-numbers/58374 "2006-04-21T00:01:52Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![dpitman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/a9adbd/32.png) [@dpitman](https://www.ruby-forum.com/u/dpitman)\ **Post date:** [April 21, 2006, 12:01am UTC](https://www.ruby-forum.com/t/xml-parser-with-file-names-and-line-numbers/58374/1 "2006-04-21T00:01:52Z")
Howdy, Is there a Ruby XML parser that includes the file name and line number for elements? Thanks, David ---
**Author:** ![dpitman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/a9adbd/32.png) [@dpitman](https://www.ruby-forum.com/u/dpitman)\ **Post date:** [April 21, 2006, 11:42am UTC](https://www.ruby-forum.com/t/xml-parser-with-file-names-and-line-numbers/58374/2 "2006-04-21T11:42:19Z")
2006/4/21, David P. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid): > Howdy, > > Is there a Ruby XML parser that includes the file name and line number for > elements? What exactly do you mean by that? AFAIK there is no place to store this info in DOM so… robert ---
**Author:** ![dpitman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/a9adbd/32.png) [@dpitman](https://www.ruby-forum.com/u/dpitman)\ **Post date:** [April 21, 2006, 2:22pm UTC](https://www.ruby-forum.com/t/xml-parser-with-file-names-and-line-numbers/58374/3 "2006-04-21T14:22:57Z")
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Robert K. wrote: > 2006/4/21, David P. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid): > > > Howdy, > > > > Is there a Ruby XML parser that includes the file name and line number for > > elements? > > What exactly do you mean by that? AFAIK there is no place to store > this info in DOM so… It seems like this would be possible with a SAXParser when you’re scanning the document to be able to grab what lineno an element is on when it starts an element. Zach -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.1 (GNU/Linux) Comment: Using GnuPG with Thunderbird - [http://enigmail.mozdev.org](http://enigmail.mozdev.org) iD8DBQFESM+EMyx0fW1d8G0RAk7tAJ4m+U76yd9Mrb3XQYR+lQ8HqFaHpwCeNmYp m1EsIM36/YOm5JHD6Ke1f9E= =KWbP -----END PGP SIGNATURE----- ---
**Author:** ![dpitman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/a9adbd/32.png) [@dpitman](https://www.ruby-forum.com/u/dpitman)\ **Post date:** [April 21, 2006, 5:22pm UTC](https://www.ruby-forum.com/t/xml-parser-with-file-names-and-line-numbers/58374/4 "2006-04-21T17:22:27Z")
It is possible with a SAX parser in Java, but the SAX parser in rexml does not include file/line information in the “PullEvent” as far as I can tell. I guess rexml is the only XML parser currently under development for ruby. ---
**Author:** ![dpitman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/a9adbd/32.png) [@dpitman](https://www.ruby-forum.com/u/dpitman)\ **Post date:** [April 21, 2006, 5:31pm UTC](https://www.ruby-forum.com/t/xml-parser-with-file-names-and-line-numbers/58374/5 "2006-04-21T17:31:44Z")
David P. wrote: > It is possible with a SAX parser in Java, but the SAX parser in rexml does > not include file/line information in the “PullEvent” as far as I can tell. > > I guess rexml is the only XML parser currently under development for ruby. No, ruby-libxml is in development. I know because I am an active “talker” on the ruby-libxml mailing list. [http://rubyforge.org/projects/libxml/](http://rubyforge.org/projects/libxml/) I switched from REXML to libxml because libxml is blazing fast. Zach ---
**Author:** ![dpitman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/a9adbd/32.png) [@dpitman](https://www.ruby-forum.com/u/dpitman)\ **Post date:** [April 21, 2006, 5:47pm UTC](https://www.ruby-forum.com/t/xml-parser-with-file-names-and-line-numbers/58374/6 "2006-04-21T17:47:35Z")
Zach, Yep… libxml does the trick with: XML::Parser.default\_line\_numbers = true … element.line\_number element.doc.filename Thanks, David ---
**Author:** ![dpitman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/a9adbd/32.png) [@dpitman](https://www.ruby-forum.com/u/dpitman)\ **Post date:** [April 21, 2006, 11:36pm UTC](https://www.ruby-forum.com/t/xml-parser-with-file-names-and-line-numbers/58374/7 "2006-04-21T23:36:08Z")
On Fri, 2006-04-21 at 00:01, David P. wrote: > Howdy, > > Is there a Ruby XML parser that includes the file name and line number for > elements? XML does not have the concept of a line. XML deals only with describing data and structure, not formatting. Carriage returns and line feeds are considered to be whitespace. That is why true XML editors use separate style sheets, like CSS, XSL-FO, or FOSI, to format XML documents. If you have an XML document, process it in some way, for example just by parsing it and saving it, any carriage returns and line feeds may have been removed. The parser may even add new ones. Whitespace is guaranteed to be preserved in CDATA sections only. You might find it more useful to count the elements themselves. That way the numbers won’t change just because you open a file in an editor and look at it. Elements do not have file names either. What is it you want to do? /Henrik – [http://kallokain.blogspot.com/](http://kallokain.blogspot.com/) - Blogging from the trenches of software development [http://www.henrikmartensson.org/](http://www.henrikmartensson.org/) - Reflections on software development [http://tocsim.rubyforge.com/](http://tocsim.rubyforge.com/) - Process simulation [http://testunitxml.rubyforge.org/](http://testunitxml.rubyforge.org/) - XML test framework [http://declan.rubyforge.org/](http://declan.rubyforge.org/) - Declarative XML processing ---
**Author:** ![dpitman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/a9adbd/32.png) [@dpitman](https://www.ruby-forum.com/u/dpitman)\ **Post date:** [April 22, 2006, 12:10am UTC](https://www.ruby-forum.com/t/xml-parser-with-file-names-and-line-numbers/58374/8 "2006-04-22T00:10:12Z")
Henrik, I’ve already got a solution to the issue. libxml-ruby has the functionality I need. One of my projects is SiteMap ( [http://rubyforge.org/projects/sitemap](http://rubyforge.org/projects/sitemap) ) which is a Domain Specific Language that descripts web site navigation, access control, link names, etc. SiteMap allows the designer to imbed Ruby code (e.g., to test access control, etc.) It would be nice to have the file/line of the generated methods in stack traces, etc. Thanks, David ---
**Author:** ![dpitman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/a9adbd/32.png) [@dpitman](https://www.ruby-forum.com/u/dpitman)\ **Post date:** [April 21, 2006, 5:59pm UTC](https://www.ruby-forum.com/t/xml-parser-with-file-names-and-line-numbers/58374/9 "2006-04-21T17:59:55Z")
On Apr 21, 2006, at 11:21 AM, David P. wrote: > It is possible with a SAX parser in Java, but the SAX parser in > rexml does > not include file/line information in the “PullEvent” as far as I > can tell. > > I guess rexml is the only XML parser currently under development > for ruby. Well, there is xampl-pp that I wrote. It doesn’t change often, that’s true, but I _use_ it a lot. The most recent version is bundled with xampl (see my signature for where). Xampl-pp is a pull parser. And it keeps track of line and column as best it can (and yes, it can get the column wrong, especially if UTF is involved (it is sometimes more of a byte count than a character count), but the line count is normally pretty good). The instance variable @input in the parser is a bit of a funny thing, but if it is a file, then you can use the File methods (e.g. path) and that’ll work – the trouble is that @input isn’t exposed, so… There are two ways in which the pull parser can be used: as an object that parses and manipulated by calling methods on it, or, alternatively, by extending the parser with actions. I use both techniques, sometimes at the same time – this can be interesting. Anyway, you can either re-open Xampl\_PP and define an accessor for @input, or you can extend and it is right there for you. I’ve never exposed a reader to @input because mucking with it would be a very very bad idea. Have you looked at the libxml wrapper? It probably provides that information. Cheers, Bob > > > > > > > > scanning > > =KWbP > > -----END PGP SIGNATURE----- * * * Bob H. – blogs at \<[http://www.recursive.ca/](http://www.recursive.ca/) hutch/\> Recursive Design Inc. – [http://www.recursive.ca/](http://www.recursive.ca/) Raconteur – [http://www.raconteur.info/](http://www.raconteur.info/) xampl for Ruby – [http://rubyforge.org/projects/xampl/](http://rubyforge.org/projects/xampl/)