On Tue, May 11, 2010 at 6:34 PM, Jonathan Rockway <j...@jrock.us> wrote:
>
> * On Tue, May 11 2010, Klaus wrote:
> > However, unlike XML::Twig, XML::Reader does not rely on callback
> > functions to parse the XML. With XML::Reader you loop over the
> > XML-document yourself and the resulting XML-elements (and/or
> > XML-subtrees) are represented in text format. This style of processing
> > XML is similar to the classic pattern:
> >
> > "open my $fh, '<', 'file.txt'; while (<$fh>) { do_sth($_); } close $fh;"
>
> FWIW, it's very easy to make callback-based code look like an iterator.
> Here's an example script.
>
> use strict;
> use warnings;
> use feature ':5.10';
>
> use Coro;
> use Coro::Handle;
> use Coro::Channel;
> [...]
Thanks, I have never heard of "Coro", "Coro::Handle" or "Coro::Channel".
Sounds interesting, I will look into it.
> So I'm not sure there's a point in writing a module just to be
> loop-driven instead of callback-driven; it's easy to convert
> callback-based code to "blocking" code.
>
> When in doubt, if you are trying to write something reusable, make it
> callback-driven instead of blocking. Then the consumer can easily
> choose how to use it.
I agree very much, it's all about informed choices.
I say that the aproach should always be to use
existing, long-standing, well-tested modules first before using XML::Reader.
That's why I commented "...take the advice of Tad McClellan and
John Bokma first..." on comp.lang.perl.misc, subject "Get XML content
using XML::Twig"
http://groups.google.com/group/comp.lang.perl.misc/msg/7b820ef7eac4cbab
Here is the gist of the discussion:
> On 21 avr, 14:35, alwaysonnet
> <kalyanrajsi...<http://groups.google.com/groups/unlock?_done=/group/comp.lang.perl.misc/browse_frm/thread/cb0f941567d152b6/d88b15bb005e9edf%3Flnk%3Dgst%26q%3Dxml%253A%253Areader%26&msg=019902ffdfd1f90c>
@gmail.com> wrote:
> > I'm trying to parse the XML using XML::Twig Module as my XML
> > could be very large to handle using XML::Simple.
> [...]
> On 21 avr, 15:13, Tad McClellan <ta...@seesig.invalid> wrote:
> > What have you tried so far?
> > If you show us your broken code we will help you fix it.
> [...]
> On 21 avr, 15:49, John Bokma <j...@castleamber.com> wrote:
> > For very simple things like this I would (probably, based on what
> > I just read) use XML::SAX or (even) XML::Parser. Regarding the
> > latter, http://johnbokma.com/perl/ has some simple examples
> > under "XML Processing using Perl"
> [...]
> On 22 avr, 11:08, Klaus <klau...@gmail.com> wrote:
> > take the advice of Tad McClellan and John Bokma first.
> > If, for whatever reason, you can't follow their advice, (and, for
> > whatever reason, you can't use XML::Twig either) there is always
> > my "shameless plug"XML::Reader:
In addition to that, I learned soon after, that there exists an excellent
article: "Ways to Rome: Processing XML with Perl"
> On 22 avr, 11:44, <redgrittybr...@spamweary.invalid> wrote:
> > For very arge XML files, the obvious approach to consider is any
> > SAX parser. Perl SAX modules I've used before include
> > XML::Parser and XML::SAX. Have you Googled for "Perl SAX"
> > and searched CPAN for SAX? I recommend you read this
> > http://xmltwig.com/article/ways_to_rome/ways_to_rome.html
And now I have learned that it is easy to convert callback-based code
to "blocking" code. -- Thanks for this.
As I said, it's all about informed choices, I will let everybody (who
considers
using XML::Reader) know about these choices.
Regards,
Klaus
