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Raku bindings to the libxml2 native library

[Raku LibXML Project] / [LibXML Module] / PI

class LibXML::PI

LibXML Processing Instructions


use LibXML::Document;
use LibXML::PI;
# Only methods specific to Processing Instruction nodes are listed here,
# see the LibXML::Node documentation for other methods

my LibXML::Document $dom .= new;
my LibXML::PI $pi = $dom.createProcessingInstruction("abc");

$pi.setData( $data_string );
$pi.setData( name=>string_value [...] );

$ ~~ s/xxx/yyy/; # Stringy Interface - see LibXML::Text


Processing instructions are implemented with LibXML with read and write access. The PI data is the PI without the PI target (as specified in XML 1.0 [17]) as a string. This string can be accessed with getData as implemented in LibXML::Node.

Many processing instructions have attribute like data. Therefore setData() provides, in addition to the DOM spec, the passing of named parameters. So the code segment:

my LibXML::PI $pi = $dom.createProcessingInstruction("abc");
$pi.setData(foo=>'bar', foobar=>'foobar');
$dom.appendChild( $pi );

will result the following PI in the DOM:

<?abc foo="bar" foobar="foobar"?>

Which is how it is specified in the DOM specification. This three step interface creates a temporary Raku object. This can be avoided while using the insertProcessingInstruction() method. Instead of the three calls described above, the call

$dom.insertProcessingInstruction("abc",'foo="bar" foobar="foobar"');

will have the same result as above.

LibXML::PI’s implementation of setData() documented below differs a bit from the standard version as available in LibXML::Node:


method setData

multi method setData( Str $data_string ) returns Mu
multi method setData( %params ) returns Mu

This method allows one to change the content data of a PI. Additionally to the interface specified for DOM Level2, the method provides a named parameter interface to set the data. This parameter list is converted into a string before it is appended to the PI.

2001-2007, Ltd.

2002-2006, Christian Glahn.

2006-2009, Petr Pajas.


This program is free software; you can redistribute it and/or modify it under the terms of the Artistic License 2.0