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Re: sub that finds ancestor elements

by tobyink (Abbot)
on Sep 13, 2012 at 02:00 UTC ( #993341=note: print w/replies, xml ) Need Help??

in reply to sub that finds ancestor elements

Code using XML::Simple rarely ends up being simple. It would be much easier if you used XML::LibXML...

#!/usr/bin/perl use feature ":5.14"; use warnings FATAL => qw(all); use strict; use XML::LibXML 2; my $x = XML::LibXML::->load_xml(string => <<'END'); <classes name="Panoply::BAR"> <public_methods> <members name="BAR" const="no" kind="function" protection="public +" static="no" virtualness="non_virtual" volatile="no"> <parameters declaration_name="pciReg" type="Register::Ptr" /> </members> </public_methods> <enums> <members name="ObjectState" kind="enum" protection="public" stati +c="no" virtualness="non_virtual"> <values name="NEW"> </values> <values name="REFRESHED"> </values> <values name="DIRTY"> </values> </members> </enums> </classes> END sub _universal_find { my $text = shift; join '|', "//$text", # Element name "//*/\@$text", # Attribute name "//*/text()[.='$text']", # Element contents "//*/\@*[.='$text']", # Attribute value } my $coolNodeName = sub { ($_[0]->isa('XML::LibXML::Attr')?'@':'').$_[0 +]->nodeName }; for my $text (qw[ parameters pciReg DIRTY ]) { say "Search for '$text'..."; for my $node ($x->findnodes( _universal_find($text) )) { say join ' => ', $node->findnodes("ancestor::*")->map(sub { $coolNodeName-> +($_) }), $coolNodeName->($node), } say ""; } __END__ Search for 'parameters'... classes => public_methods => members => parameters Search for 'pciReg'... classes => public_methods => members => parameters => @declaration_nam +e Search for 'DIRTY'... classes => enums => members => values => @name

(Update: improved _universal_find to return attribute nodes instead of element nodes when attribute nodes are more appropriate; improved output.)

perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

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Re^2: sub that finds ancestor elements
by jccunning (Acolyte) on Sep 13, 2012 at 19:23 UTC
    I have had no success installing XML::LibXML 2 maybe you can help. I am on Windows 7 enterprise 32-bit, activestate perl 5.14. Tried installing "ppm install XML::LibXML::2.0004 but error said no package available.
Re^2: sub that finds ancestor elements
by tobyink (Abbot) on Sep 13, 2012 at 20:52 UTC
    Why the colons between the module name and version number? (I doubt you need to specify the version number at all - ppm presumably defaults to the latest version available.)
    perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'
      When I install using "ppm install XML-LibXML" then version 1.70 of XML-LibXML is installed as the latest. Your script indicated "use XML::LibXML 2;". Of course, I get error that version 2 is required.

        Replace this:

        $node->findnodes("ancestor::*")->map(sub { $coolNodeName->($_) })

        With this:

        (map { $coolNodeName->($_) } $node->findnodes("ancestor::*"))

        ... and you should be able to use XML::LibXML 1.70.

        perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

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[Corion]: Hi marto!
[Corion]: I just found out that in $current_top_prior ity_project , the part I am in is not even in the top three worries. That's somewhat bad, not because I'm happy with being a top worry but because that means that I don't even know how bad the rest ...
[Corion]: ... of the situation is :-)
[marto]: it's good to know that things can always get worse :P
[hippo]: Ignorance can be bliss

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