Re^3: Parsing XML

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Re^4: Parsing XML by Anonymous Monk on Sep 02, 2016 at 16:27 UTC
The documentation isn't very friendly, I trying this way, but I am getting a lot of XML instead of just the "999": `... my $t= XML::Twig->new( twig_handlers => { 'CustDetails' => sub { $_->first_child('C +ustomerId')->text(), } } ) ->parse($test_xml); warn Dumper $t;` [download]	[reply] [d/l]
Re^5: Parsing XML by Corion (Patriarch) on Sep 02, 2016 at 16:37 UTC
Have you tried searching for the "text" or "content" method? Maybe it does what you need? You don't show what output you actually get, and I'm really bad at guessing. Maybe you can show what output you get for which input. Personally, I found it always quite enlightening to also look at the value of `->path` to see which node is output, and also maybe find out why.	[reply] [d/l]
Re^4: Parsing XML by Anonymous Monk on Sep 02, 2016 at 17:49 UTC
Yeah, this worked: `my $val; my $t= XML::Twig->new( twig_handlers => { 'CustDetails' => sub { $val = $_->first_child('Custome +rId')->text(), } } ) ->parse($test_xml); print $val;` [download] I wish it was less complicated for such a simple example on how to use XML::Twig - Could it be simpler just using RegExp? Thank you!	[reply] [d/l]
Re^5: Parsing XML by AnomalousMonk (Archbishop) on Sep 02, 2016 at 18:30 UTC
I wish it was less complicated for such a simple example on how to use XML::Twig - Could it be simpler just using RegExp? A simple example may simply hide the tangled inherent complexity of XML. Heed the wise advice of Corion. Resist the temptation to use regexes; that way lies madness! Give a man a fish: `<%-{-{-{-<`	[reply] [d/l]
Re^4: Parsing XML by Anonymous Monk on Sep 02, 2016 at 17:22 UTC
Hi, this is what I am getting: #!/usr/bin/perl use strict; use warnings; use XML::Twig; use Data::Dumper; my $test_xml = qq\|<?xml version="1.0" encoding="ISO-8859-1"?> <CustDetails> <CustName>Unix</CustName> <CustomerId>999</CustomerId> <Age>28</Age> </CustDetails> \|; my $t= XML::Twig->new( twig_handlers => { 'CustDetails' => sub { $_->first_child('C +ustomerId')->text(), } } ) ->parse($test_xml); warn Dumper $t; # I am trying to get this: 999 # in instead, I am getting this: =code $VAR1 = bless( { 'twig_xmldecl' => { 'version' => '1.0', 'standalone' => undef, 'encoding' => 'ISO-8859-1' }, 'twig_keep_pi' => 1, 'twig_current' => undef, 'twig_autoflush' => 1, 'twig_space_policy' => { 'CustDetails' => 0 }, 'twig_entity_list' => bless( { 'updated' => 0, 'entities' => {} }, 'XML::Twig::Entity_list +' ), 'twig_do_not_escape_amp_in_atts' => 0, 'twig' => $VAR1, 'NoExpand' => 0, 'twig_keep_comments' => 1, 'twig_discard_spaces' => 1, '_twig_context_stack' => undef, 'twig_elt_class' => 'XML::Twig::Elt', 'twig_id' => 'id', 'twig_parsing' => undef, 'Non_Expat_Options' => { 'NoLWP' => 1, 'Non_Expat_Options' => 1, '_HNDL_TYPES' => 1, 'Handlers' => 1, 'Style' => 1 }, 'Handlers' => { 'CdataEnd' => sub { "DUMMY" }, 'Default' => sub { "DUMMY" }, 'CdataStart' => sub { "DUMMY" }, 'Start' => sub { "DUMMY" }, 'Comment' => sub { "DUMMY" }, 'Entity' => sub { "DUMMY" }, 'End' => sub { "DUMMY" }, 'Final' => sub { "DUMMY" }, 'Doctype' => sub { "DUMMY" }, 'Char' => sub { "DUMMY" }, 'Init' => sub { "DUMMY" }, 'Attlist' => sub { "DUMMY" }, 'Element' => sub { "DUMMY" }, 'ExternEnt' => sub { "DUMMY" }, 'XMLDecl' => sub { "DUMMY" }, 'Proc' => sub { "DUMMY" } }, 'twig_ext_ent_handler' => sub { "DUMMY" }, 'trailing_spaces' => ' ', 'twig_handlers' => { 'xpath_handler' => { 'Age' => undef, 'CustomerId' => + undef, 'CustName' => u +ndef, '*' => undef, 'CustDetails' = +> [ + { + 'trigger' => sub { "DUMMY" }, + 'handler' => sub { "DUMMY" }, + 'test_on_text' => 0, + 'path' => 'CustDetails', + 'score' => { + 'steps' => 1, + 'type' => 3, + 'anchored' => 0 + }, + 'tag' => 'CustDetails' + } +] }, 'handlers' => { 'string' => { 'CustDet +ails' => $VAR1->{'twig_handlers'}{'xpath_handler'}{'CustDetails'}[0]{ +'handler'} } } }, 'TwigHandlers' => { 'CustDetails' => $VAR1->{'twig_ha +ndlers'}{'xpath_handler'}{'CustDetails'}[0]{'handler'} }, 'extra_data' => '', 'Pkg' => 'XML::Twig', '_HNDL_TYPES' => { 'CdataEnd' => sub { "DUMMY" }, 'Start' => sub { "DUMMY" }, 'Entity' => sub { "DUMMY" }, 'ExternEntFin' => sub { "DUMMY" }, 'End' => sub { "DUMMY" }, 'Final' => 1, 'Doctype' => sub { "DUMMY" }, 'Char' => sub { "DUMMY" }, 'Init' => 1, 'XMLDecl' => sub { "DUMMY" }, 'Default' => sub { "DUMMY" }, 'CdataStart' => sub { "DUMMY" }, 'Comment' => sub { "DUMMY" }, 'Unparsed' => sub { "DUMMY" }, 'ExternEnt' => sub { "DUMMY" }, 'Element' => sub { "DUMMY" }, 'Attlist' => sub { "DUMMY" }, 'DoctypeFin' => sub { "DUMMY" }, 'Notation' => sub { "DUMMY" }, 'Proc' => sub { "DUMMY" } }, 'twig_keep_encoding' => 0, 'twig_dtd_handler' => undef, 'twig_in_pcdata' => 0, 'twig_parser' => undef, 'twig_stored_spaces' => ' ', 'twig_root' => bless( { 'gi' => '6', 'first_child' => bless( { 'next_s +ibling' => bless( { + 'next_sibling' => bless( { + 'parent' => $VAR1->{'twig_ +root'}, + 'gi' => '9', + 'prev_sibling' => $VAR1->{ +'twig_root'}{'first_child'}{'next_sibling'}, + 'first_child' => bless( { + 'p +arent' => $VAR1->{'twig_root'}{'first_child'}{'next_sibling'}{'next_s +ibling'}, + 'g +i' => 1, + 'p +cdata' => '28' + }, ' +XML::Twig::Elt' ), + 'att' => {}, + 'last_child' => $VAR1->{'t +wig_root'}{'first_child'}{'next_sibling'}{'next_sibling'}{'first_chil +d'} + }, 'XML::Twig::Elt' ), + 'parent' => $VAR1->{'twig_root'}, + 'gi' => '8', + 'prev_sibling' => $VAR1->{'twig_root'}{'first_child +'}, + 'first_child' => bless( { + 'parent' => $VAR1->{'twig_r +oot'}{'first_child'}{'next_sibling'}, + 'gi' => 1, + 'pcdata' => '999' + }, 'XML::Twig::Elt' ), + 'att' => {}, + 'last_child' => $VAR1->{'twig_root'}{'first_child'} +{'next_sibling'}{'first_child'} + }, 'XML::Twig::Elt' ), 'parent +' => $VAR1->{'twig_root'}, 'gi' => + '7', 'first_ +child' => bless( { + 'parent' => $VAR1->{'twig_root'}{'first_child'}, + 'gi' => 1, + 'pcdata' => 'Unix' + }, 'XML::Twig::Elt' ), 'att' = +> {}, 'last_c +hild' => $VAR1->{'twig_root'}{'first_child'}{'first_child'} }, 'XML:: +Twig::Elt' ), 'att' => {}, 'last_child' => $VAR1->{'twig_r +oot'}{'first_child'}{'next_sibling'}{'next_sibling'}, 'twig' => $VAR1 }, 'XML::Twig::Elt' ) }, 'XML::Twig' ); =cut [download] }, DUMMYparent	[reply] [d/l]
Re^5: Parsing XML by Corion (Patriarch) on Sep 02, 2016 at 17:36 UTC
That's the output you get from `warn Dumper $t;` [download] Why do you do that when you don't know what happens there? Maybe you want to store or print a value when XML::Twig invokes the callback for your node, in the following callback? `'CustDetails' => sub { $_->first_child('CustomerId')->text(), }` [download] Maybe something like the following: `'CustDetails' => sub { print "The first customer has the following det +ails: " . $_->first_child('CustomerId')->text(), }` [download]	[reply] [d/l] [select]

...
my $t= XML::Twig->new( twig_handlers => 
                           { 'CustDetails' => sub { $_->first_child('C
+ustomerId')->text(), } }
                       )
                  ->parse($test_xml);
warn Dumper $t;
[download]

[reply]
[d/l]

Have you tried searching for the "text" or "content" method? Maybe it does what you need?

You don't show what output you actually get, and I'm really bad at guessing.

Maybe you can show what output you get for which input.

Personally, I found it always quite enlightening to also look at the value of ->path to see which node is output, and also maybe find out why.

[reply]
[d/l]

my $val;
my $t= XML::Twig->new( twig_handlers => 
              { 'CustDetails' => sub { $val = $_->first_child('Custome
+rId')->text(), } }
                       )
                  ->parse($test_xml);
print $val;
[download]

[reply]
[d/l]

I wish it was less complicated for such a simple example on how to use XML::Twig - Could it be simpler just using RegExp?

A simple example may simply hide the tangled inherent complexity of XML. Heed the wise advice of Corion. Resist the temptation to use regexes; that way lies madness!

Give a man a fish: <%-{-{-{-<

[reply]
[d/l]

#!/usr/bin/perl

use strict;
use warnings;
use XML::Twig;
use Data::Dumper;


my $test_xml =  qq|<?xml version="1.0" encoding="ISO-8859-1"?>
<CustDetails>
<CustName>Unix</CustName>
<CustomerId>999</CustomerId>
<Age>28</Age>
</CustDetails>
|;


my $t= XML::Twig->new( twig_handlers => 
                           { 'CustDetails' => sub { $_->first_child('C
+ustomerId')->text(), } }
                       )
                  ->parse($test_xml);
warn Dumper $t;

# I am trying to get this: 999

# in instead, I am getting this:

=code
$VAR1 = bless( {
                 'twig_xmldecl' => {
                                   'version' => '1.0',
                                   'standalone' => undef,
                                   'encoding' => 'ISO-8859-1'
                                 },
                 'twig_keep_pi' => 1,
                 'twig_current' => undef,
                 'twig_autoflush' => 1,
                 'twig_space_policy' => {
                                        'CustDetails' => 0
                                      },
                 'twig_entity_list' => bless( {
                                              'updated' => 0,
                                              'entities' => {}
                                            }, 'XML::Twig::Entity_list
+' ),
                 'twig_do_not_escape_amp_in_atts' => 0,
                 'twig' => $VAR1,
                 'NoExpand' => 0,
                 'twig_keep_comments' => 1,
                 'twig_discard_spaces' => 1,
                 '_twig_context_stack' => undef,
                 'twig_elt_class' => 'XML::Twig::Elt',
                 'twig_id' => 'id',
                 'twig_parsing' => undef,
                 'Non_Expat_Options' => {
                                          'NoLWP' => 1,
                                          'Non_Expat_Options' => 1,
                                          '_HNDL_TYPES' => 1,
                                          'Handlers' => 1,
                                          'Style' => 1
                                        },
                 'Handlers' => {
                                 'CdataEnd' => sub { "DUMMY" },
                                 'Default' => sub { "DUMMY" },
                                 'CdataStart' => sub { "DUMMY" },
                                 'Start' => sub { "DUMMY" },
                                 'Comment' => sub { "DUMMY" },
                                 'Entity' => sub { "DUMMY" },
                                 'End' => sub { "DUMMY" },
                                 'Final' => sub { "DUMMY" },
                                 'Doctype' => sub { "DUMMY" },
                                 'Char' => sub { "DUMMY" },
                                 'Init' => sub { "DUMMY" },
                                 'Attlist' => sub { "DUMMY" },
                                 'Element' => sub { "DUMMY" },
                                 'ExternEnt' => sub { "DUMMY" },
                                 'XMLDecl' => sub { "DUMMY" },
                                 'Proc' => sub { "DUMMY" }
                               },
                 'twig_ext_ent_handler' => sub { "DUMMY" },
                 'trailing_spaces' => '
',
                 'twig_handlers' => {
                                    'xpath_handler' => {
                                                       'Age' => undef,
                                                       'CustomerId' =>
+ undef,
                                                       'CustName' => u
+ndef,
                                                       '*' => undef,
                                                       'CustDetails' =
+> [
                                                                      
+  {
                                                                      
+    'trigger' => sub { "DUMMY" },
                                                                      
+    'handler' => sub { "DUMMY" },
                                                                      
+    'test_on_text' => 0,
                                                                      
+    'path' => 'CustDetails',
                                                                      
+    'score' => {
                                                                      
+               'steps' => 1,
                                                                      
+               'type' => 3,
                                                                      
+               'anchored' => 0
                                                                      
+             },
                                                                      
+    'tag' => 'CustDetails'
                                                                      
+  }
                                                                      
+]
                                                     },
                                    'handlers' => {
                                                  'string' => {
                                                              'CustDet
+ails' => $VAR1->{'twig_handlers'}{'xpath_handler'}{'CustDetails'}[0]{
+'handler'}
                                                            }
                                                }
                                  },
                 'TwigHandlers' => {
                                     'CustDetails' => $VAR1->{'twig_ha
+ndlers'}{'xpath_handler'}{'CustDetails'}[0]{'handler'}
                                   },
                 'extra_data' => '',
                 'Pkg' => 'XML::Twig',
                 '_HNDL_TYPES' => {
                                    'CdataEnd' => sub { "DUMMY" },
                                    'Start' => sub { "DUMMY" },
                                    'Entity' => sub { "DUMMY" },
                                    'ExternEntFin' => sub { "DUMMY" },
                                    'End' => sub { "DUMMY" },
                                    'Final' => 1,
                                    'Doctype' => sub { "DUMMY" },
                                    'Char' => sub { "DUMMY" },
                                    'Init' => 1,
                                    'XMLDecl' => sub { "DUMMY" },
                                    'Default' => sub { "DUMMY" },
                                    'CdataStart' => sub { "DUMMY" },
                                    'Comment' => sub { "DUMMY" },
                                    'Unparsed' => sub { "DUMMY" },
                                    'ExternEnt' => sub { "DUMMY" },
                                    'Element' => sub { "DUMMY" },
                                    'Attlist' => sub { "DUMMY" },
                                    'DoctypeFin' => sub { "DUMMY" },
                                    'Notation' => sub { "DUMMY" },
                                    'Proc' => sub { "DUMMY" }
                                  },
                 'twig_keep_encoding' => 0,
                 'twig_dtd_handler' => undef,
                 'twig_in_pcdata' => 0,
                 'twig_parser' => undef,
                 'twig_stored_spaces' => '
',
                 'twig_root' => bless( {
                                       'gi' => '6',
                                       'first_child' => bless( {
                                                               'next_s
+ibling' => bless( {
                                                                      
+                  'next_sibling' => bless( {
                                                                      
+                                           'parent' => $VAR1->{'twig_
+root'},
                                                                      
+                                           'gi' => '9',
                                                                      
+                                           'prev_sibling' => $VAR1->{
+'twig_root'}{'first_child'}{'next_sibling'},
                                                                      
+                                           'first_child' => bless( {
                                                                      
+                                                                   'p
+arent' => $VAR1->{'twig_root'}{'first_child'}{'next_sibling'}{'next_s
+ibling'},
                                                                      
+                                                                   'g
+i' => 1,
                                                                      
+                                                                   'p
+cdata' => '28'
                                                                      
+                                                                 }, '
+XML::Twig::Elt' ),
                                                                      
+                                           'att' => {},
                                                                      
+                                           'last_child' => $VAR1->{'t
+wig_root'}{'first_child'}{'next_sibling'}{'next_sibling'}{'first_chil
+d'}
                                                                      
+                                         }, 'XML::Twig::Elt' ),
                                                                      
+                  'parent' => $VAR1->{'twig_root'},
                                                                      
+                  'gi' => '8',
                                                                      
+                  'prev_sibling' => $VAR1->{'twig_root'}{'first_child
+'},
                                                                      
+                  'first_child' => bless( {
                                                                      
+                                          'parent' => $VAR1->{'twig_r
+oot'}{'first_child'}{'next_sibling'},
                                                                      
+                                          'gi' => 1,
                                                                      
+                                          'pcdata' => '999'
                                                                      
+                                        }, 'XML::Twig::Elt' ),
                                                                      
+                  'att' => {},
                                                                      
+                  'last_child' => $VAR1->{'twig_root'}{'first_child'}
+{'next_sibling'}{'first_child'}
                                                                      
+                }, 'XML::Twig::Elt' ),
                                                               'parent
+' => $VAR1->{'twig_root'},
                                                               'gi' =>
+ '7',
                                                               'first_
+child' => bless( {
                                                                      
+                 'parent' => $VAR1->{'twig_root'}{'first_child'},
                                                                      
+                 'gi' => 1,
                                                                      
+                 'pcdata' => 'Unix'
                                                                      
+               }, 'XML::Twig::Elt' ),
                                                               'att' =
+> {},
                                                               'last_c
+hild' => $VAR1->{'twig_root'}{'first_child'}{'first_child'}
                                                             }, 'XML::
+Twig::Elt' ),
                                       'att' => {},
                                       'last_child' => $VAR1->{'twig_r
+oot'}{'first_child'}{'next_sibling'}{'next_sibling'},
                                       'twig' => $VAR1
                                     }, 'XML::Twig::Elt' )
               }, 'XML::Twig' );
=cut
[download]

[reply]
[d/l]

That's the output you get from

warn Dumper $t;
[download]

Why do you do that when you don't know what happens there?

Maybe you want to store or print a value when XML::Twig invokes the callback for your node, in the following callback?

'CustDetails' => sub { $_->first_child('CustomerId')->text(), }
[download]

Maybe something like the following:

'CustDetails' => sub { print "The first customer has the following det
+ails: " . $_->first_child('CustomerId')->text(), }
[download]

[reply]
[d/l]
[select]