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XML::LibXML::Pattern

Section: User Contributed Perl Documentation (3pm)

Updated: 2014-04-12

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NAME

XML::LibXML::Pattern - XML::LibXML::Pattern - interface to libxml2 XPath patterns

SYNOPSIS

use XML::LibXML; my $pattern = XML::LibXML::Pattern->new('/x:html/x:body//x:div', { 'x' => 'http://www.w3.org/1999/xhtml' }); # test a match on an XML::LibXML::Node $node

if ($pattern->matchesNode($node)) { ... }

# or on an XML::LibXML::Reader

if ($reader->matchesPattern($pattern)) { ... }

# or skip reading all nodes that do not match

print $reader->nodePath while $reader->nextPatternMatch($pattern);

$pattern = XML::LibXML::Pattern->new( pattern, { prefix => namespace_URI, ... } ); $bool = $pattern->matchesNode($node);

@]

DESCRIPTION

This is a perl interface to libxml2's pattern matching support http://xmlsoft.org/html/libxml-pattern.html. This feature requires recent versions of libxml2.

Patterns are a small subset of XPath language, which is limited to (disjunctions of) location paths involving the child and descendant axes in abbreviated form as described by the extended BNF given below:

For readability, whitespace may be used in selector XPath expressions even though not explicitly allowed by the grammar: whitespace may be freely added within patterns before or after any token, where

Note that no predicates or attribute tests are allowed.

Patterns are particularly useful for stream parsing provided via the interface.
new()

The constructor of a pattern takes a pattern expression (as described by the BNF grammar above) and an optional HASH reference mapping prefixes to namespace URIs. The method returns a compiled pattern object.

Note that if the document has a default namespace, it must still be given an prefix in order to be matched (as demanded by the XPath 1.0 specification). For example, to match an element , one should use a pattern like this:

$pattern = XML::LibXML::Pattern->new( 'foo:a', { foo => 'http://foo.bar' });

@] :

matchesNode($node)

Given an XML::LibXML::Node object, returns a true value if the node is matched by the compiled pattern expression.

:

SEE ALSO

XML::LibXML::Reader for other methods involving compiled patterns.

AUTHORS

Matt Sergeant, Christian Glahn, Petr Pajas

VERSION

2.0116

COPYRIGHT

2001-2007, AxKit.com Ltd.

2002-2006, Christian Glahn.

2006-2009, Petr Pajas.

LICENSE

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.


Index

NAME

SYNOPSIS

DESCRIPTION

SEE ALSO

AUTHORS

VERSION

COPYRIGHT

LICENSE