=head1 XML::DT a Perl XML down translate module With XML::DT, I think that: . it is simple to do simple XML processing tasks :) . it is simple to have the XML processor stored in a single variable (see example 4) . it is simple to translate XML -> Perl user controlled complex structure with a compact "-type" definition (see last section) Feedback welcome -> jj@di.uminho.pt =head1 XML::DT a Perl XML down translate module This document is also available in HTML (pod2html'ized): http://www.di.uminho.pt/~jj/perl/XML/XML-DT.readme.html . design to do simple and compact translation/processing of XML document . it includes some features of omnimark and sgmls.pm; functional approach . it includes functions to automatic build user controlled complex Perl structures (see "working with structures" section) . it was build to show my NLP Perl students that it is easy to work with XML . home page and download: http://www.di.uminho.pt/~jj/perl/XML/DT.html =head1 HOW IT WORKS: . the user must define a handler and call the basic function : dt($filename,%handler) or dtstring($string,%handler) . the handler is a HASH mapping element names to functions. Handlers can have a "-default" function , and a "-end" function . in order to make it smaller each function receives 3 args as global variables $c - contents $q - element name %v - attribute values . the default "-default" function is the identity. The function "toxml" makes the original XML text based on $c, $q and %v values. . see some advanced features in the last examples =head1 SOME simple (naive) examples: INDEX: 1. change to lowercase attribute named "a" in element "e" 2. better solution 3. make some statistics and output results in HTML (using side effects) 4. In a HTML like XML document, substitute ... by the real table of contents (a dirty solution...) 5. a more realistic example: from XML gcapaper DTD to latex WORKING WITH STRUCTURES INSTEAD OF STRINGS... 6. Build the natural Perl structure of the following document (ARRAY,HASH) 7. Multi map on... =head2 1. change to lowercase the contents of the attribute named "a" in element "e" use XML::DT ; my $filename = shift; print dt($filename, ( e => sub{ "$c" })); =head2 2. A better solution of the previous example Ex.1 wouldn't work if we have more attributes in element e. A better solution is print dt($filename, ( e => sub{ $v{a} = lc($v{a}); toxml();})); =head2 3. make some statistics and output results in HTML (using side effects) use XML::DT ; my $filename = shift; %handler=( -default => sub{$elem_counter++; $elem_table{$q}++;"";} # $q -> element name ); dt($filename,%handler); print "

We have found $elem_counter elements in document

"; print "
ELEMENTOCCURS\n"; foreach $elem (sort keys %elem_table) {print "
$elem$elem_table{$elem}\n";} print "
"; =head2 4. In a HTML like XML document, substitute ... by the real table of contents (a dirty solution...) %handler=( h1 => sub{ $index .= "\n$c"; toxml();}, h2 => sub{ $index .= "\n\t$c"; toxml();}, h3 => sub{ $index .= "\n\t\t$c"; toxml();}, contents => sub{ $c="__CLEAN__"; toxml();}, -end => sub{ $c =~ s/__CLEAN__/$index/; $c}); print dt($filename,%handler) =head2 5. a more realistic example: from XML gcapaper DTD to latex notes: . "TITLE" is processed in context dependent way! . output in ISOLATIN1 (this is dirty but my LaTeX doesn't support UNICODE) . a stack of authors was necessary because LaTeX structure was different from input structure... . this example was partially created by the function mkdtskel Perl -MXML::DT -e 'mkdtskel "f.xml"' > f.pl and took me about one hour to tune to real LaTeX/XML example. NAME gcapaper2tex.pl - a Perl script to translate XML gcapaper DTD to latex SYNOPSIS gcapaper2tex.pl mypaper.xml > mupaper.tex use XML::DT ; my $filename = shift; my $beginLatex = '\documentclass{article} \begin{document} '; my $endLatex = '\end{document}'; %handler=( '-outputenc' => 'ISO-8859-1', '-default' => sub{"$c"}, 'RANDLIST' => sub{"\\begin{itemize}$c\\end{itemize}"}, 'AFFIL' => sub{""}, # delete affiliation 'TITLE' => sub{ if(inctxt('SECTION')){"\\section{$c}"} elsif(inctxt('SUBSEC1')){"\\subsection{$c}"} else {"\\title{$c}"} }, 'GCAPAPER' => sub{"$beginLatex $c $endLatex"}, 'PARA' => sub{"$c\n\n"}, 'ADDRESS' => sub{"\\thanks{$c}"}, 'PUB' => sub{"} $c"}, 'EMAIL' => sub{"(\\texttt{$c}) "}, 'FRONT' => sub{"$c\n"}, 'AUTHOR' => sub{ push @aut, $c ; ""}, 'ABSTRACT' => sub{ sprintf('\author{%s}\maketitle\begin{abstract}%s\end{abstract}', join ('\and', @aut) , $c) }, 'CODE.BLOCK' => sub{"\\begin{verbatim}\n$c\\end{verbatim}\n"}, 'XREF' => sub{"\\cite{$v{REFLOC}}"}, 'LI' => sub{"\\item $c"}, 'BIBLIOG' =>sub{"\\begin{thebibliography}{1}$c\\end{thebibliography}\n"}, 'HIGHLIGHT' => sub{" \\emph{$c} "}, 'BIO' => sub{""}, #delete biography 'SURNAME' => sub{" $c "}, 'CODE' => sub{"\\verb!$c!"}, 'BIBITEM' => sub{"\n\\bibitem{$c"}, ); print dt($filename,%handler); =head1 WORKING WITH STRUCTURES INSTEAD OF STRINGS... the "-type" definition defines the way to build structures in each case: . "HASH" or "MAP" -> make an hash with the sub-elements; keys are the sub-element names; warn on repetitions; returns the hash reference. . "ARRAY" or "SEQ" -> make an ARRAY with the sub-elements returns an array reference. . "MULTIMAP" -> makes an HASH of ARRAY; keys are the sub-element . MMAPON(name1, ...) -> similar to HASH but accepts repetitions of the sub-elements "name1"... (and makes an array with them) . STR ->(DEFAULT) concatenates all the sub-elements returned values all the sub-element should return strings to be concatenated =head2 6. Build the natural Perl structure of the following document U.M. University of Minho 1111 1112 1113 Portugal J.Joao; J.Rocha; J.Ramalho use XML::DT; %handler = ( -default => sub{$c}, -type => { institution => 'HASH', tels => 'ARRAY' }, contacts => sub{ [ split(";",$c)] }, ); $a = dt("ex10.2.xml", %handler); $a is a reference to an HASH: { 'tels' => [ 1111, 1112, 1113 ], 'name' => 'University of Minho', 'where' => 'Portugal', 'id' => 'U.M.', 'contacts' => [ 'J.Joao', ' J.Rocha', ' J.Ramalho' ] }; =head2 7. Christmas card... We have the following address book: name0
address00
address01
name1
address10
address11
Now we are going to build a structure to store the address book and write a Christmas card to the first address of everyone #!/usr/bin/perl use XML::DT; %handler = ( -default => sub{$c}, person => sub{ mkchristmascard($c); $c}, -type => { people => 'ARRAY', person => MMAPON('address')}); $people = dt("ex11.1.xml", %handler); print $people->[0]{address}[1]; # prints address01 sub mkchristmascard{ my $x=shift; open(A,"|lpr") or die; print A <<"."; $x->{name} $x->{address}[0] Dear $x->{name} Merry Christmas from Braga Perl mongers\n . close A; }