XML::Writer 0.1 available

---

Date:    Mon, 19 Apr 1999 15:02:27 -0400 (EDT)
From:    David Megginson <david@megginson.com>
To:      Perl-XML Mailing List <perl-xml@listserv.activestate.com>
Subject: XML::Writer 0.1 available

---

I needed this, so I wrote it this morning:

      http://www.megginson.com/Software/XML-Writer-0.1.tar.gz

(I've also sent an upload to CPAN, but it might take a while to appear). Here's a very simple synopsis:

  use XML::Writer;
  use IO;

  my $output = new IO::File(">output.xml");
  my $writer = new XML::Writer($output);

  $writer->startTag("greeting",
                    "class" => "simple");
  $writer->characters("Hello, world!");
  $writer->endTag("greeting");

  $writer->end();
  $output->close();

(You can also leave out the $output argument if you want to go straight to STDOUT.)

By default, the module does a fair bit of well-formedness checking to help you catch bugs in your Perl programs -- you can turn the checking off for production use if you like to live on the wild side.

Here are the errors that the module catches so far:

• Lack of a (top-level) document element, or multiple document elements.

• Unclosed start tags.

• Misplaced delimiters in the contents of processing instructions or comments.

• Misplaced or duplicate XML declaration(s).

• Misplaced or duplicate DOCTYPE declaration(s).

• Mismatch between the document type name in the DOCTYPE declaration and the name of the document element.

• Mismatched start and end tags.

• Attempts to insert character data outside the document element.

• Duplicate attributes with the same name.

Full POD documentation and a lot of test cases in test.pl are included.

Enjoy!

---

[...]
Benjamin Holzman writes:

 > This seems to duplicate the functionality in my XML::Generator,
 > more or less.  Did you look at that module and decide it wasn't
 > appropriate?

I took a quick glance at the README, test.pl, and Generator.pm --
XML::Generator uses a very interesting approach, but (at least as far
as I read) it is quite different from the approach that I took with
XML::Writer.

XML::Generator seems to require that the entire structure be held in
memory at once, as hash or array references or what-have-you.  While
that approach can be very powerful and expressive, it is not suitable
for dealing with very large documents that cannot be held in memory
all at once.

XML::Writer is designed to align very closely with the (important)
callbacks in the Handler flavour of XML::Parser, so that it's simple
to write an identity transform:

  use XML::Parser;
  use XML::Writer;

  my $writer = new XML::Writer();

  sub start {
    my ($expat, $name, @atts) = (@_);
    $writer->startTag($name, @atts);
  }

  sub end {
    my ($expat, $name) = (@_);
    $writer->endTag($name);
  }

  sub char {
    my ($expat, $data) = (@_);
    $writer->characters($data);
  }

  my $parser = new XML::Parser(Handlers => {Start => \&start,
                                            End => \&end,
                                            Char => \&char});
  $parser->parsefile(shift);
  $writer->end();

Apologies if I have misinterpreted XML::Generator.

David

---

David Megginson                 david@megginson.com
           http://www.megginson.com/

---