# # Copyright (C) 1998, 1999 Ken MacLeod # XML::Grove::Path is free software; you can redistribute it # and/or modify it under the same terms as Perl itself. # # $Id: Path.pm,v 1.2 1999/08/17 15:01:28 kmacleod Exp $ # package XML::Grove::Path; use XML::Grove; use XML::Grove::XPointer; use UNIVERSAL; sub at_path { my $element = shift; # or Grove my $path = shift; $path =~ s|^/*||; my @path = split('/', $path); return (_at_path ($element, [@path])); } sub _at_path { my $element = shift; # or Grove my $path = shift; my $segment = shift @$path; # segment := [ type ] [ '[' index ']' ] # # strip off the first segment, finding the type and index $segment =~ m|^ ([^\[]+)? # - look for an optional type # by matching anything but '[' (?: # - don't backreference the literals \[ # - literal '[' ([^\]]+) # - index, any non-']' chars \] # - literal ']' )? # - the whole index is optional |x; my ($node_type, $instance, $match) = ($1, $2, $&); # issues: # - should assert that no chars come after index and before next # segment or the end of the query string $instance = 1 if !defined $instance; my $object = $element->xp_child ($instance, $node_type); if ($#$path eq -1) { return $object; } elsif (!$object->isa('XML::Grove::Element')) { # FIXME a location would be nice. die "\`$match' doesn't exist or is not an element\n"; } else { return (_at_path($object, $path)); } } package XML::Grove::Document; sub at_path { goto &XML::Grove::Path::at_path; } package XML::Grove::Element; sub at_path { goto &XML::Grove::Path::at_path; } 1; __END__ =head1 NAME XML::Grove::Path - return the object at a path =head1 SYNOPSIS use XML::Grove::Path; # Using at_path method on XML::Grove::Document or XML::Grove::Element: $xml_obj = $grove_object->at_path("/some/path"); # Using an XML::Grove::Path instance: $pather = XML::Grove::Path->new(); $xml_obj = $pather->at_path($grove_object); =head1 DESCRIPTION C returns XML objects located at paths. Paths are strings of element names or XML object types seperated by slash ("/") characters. Paths must always start at the grove object passed to `C'. C is B XPath, but it should become obsolete when an XPath implementation is available. Paths are like URLs /html/body/ul/li[4] /html/body/#pi[2] The path segments can be element names or object types, the objects types are named using: #element #pi #comment #text #cdata #any The `C<#any>' object type matches any type of object, it is essentially an index into the contents of the parent object. The `C<#text>' object type treats text objects as if they are not normalized. Two consecutive text objects are seperate text objects. =head1 AUTHOR Ken MacLeod, ken@bitsko.slc.ut.us =head1 SEE ALSO perl(1), XML::Grove(3) Extensible Markup Language (XML) =cut