Edit file File name : urn.pm Content :package URI::urn; # RFC 2141 use strict; use warnings; our $VERSION = '1.76'; use parent 'URI'; use Carp qw(carp); my %implementor; my %require_attempted; sub _init { my $class = shift; my $self = $class->SUPER::_init(@_); my $nid = $self->nid; my $impclass = $implementor{$nid}; return $impclass->_urn_init($self, $nid) if $impclass; $impclass = "URI::urn"; if ($nid =~ /^[A-Za-z\d][A-Za-z\d\-]*\z/) { my $id = $nid; # make it a legal perl identifier $id =~ s/-/_/g; $id = "_$id" if $id =~ /^\d/; $impclass = "URI::urn::$id"; no strict 'refs'; unless (@{"${impclass}::ISA"}) { if (not exists $require_attempted{$impclass}) { # Try to load it my $_old_error = $@; eval "require $impclass"; die $@ if $@ && $@ !~ /Can\'t locate.*in \@INC/; $@ = $_old_error; } $impclass = "URI::urn" unless @{"${impclass}::ISA"}; } } else { carp("Illegal namespace identifier '$nid' for URN '$self'") if $^W; } $implementor{$nid} = $impclass; return $impclass->_urn_init($self, $nid); } sub _urn_init { my($class, $self, $nid) = @_; bless $self, $class; } sub _nid { my $self = shift; my $opaque = $self->opaque; if (@_) { my $v = $opaque; my $new = shift; $v =~ s/[^:]*/$new/; $self->opaque($v); # XXX possible rebless } $opaque =~ s/:.*//s; return $opaque; } sub nid { # namespace identifier my $self = shift; my $nid = $self->_nid(@_); $nid = lc($nid) if defined($nid); return $nid; } sub nss { # namespace specific string my $self = shift; my $opaque = $self->opaque; if (@_) { my $v = $opaque; my $new = shift; if (defined $new) { $v =~ s/(:|\z).*/:$new/; } else { $v =~ s/:.*//s; } $self->opaque($v); } return undef unless $opaque =~ s/^[^:]*://; return $opaque; } sub canonical { my $self = shift; my $nid = $self->_nid; my $new = $self->SUPER::canonical; return $new if $nid !~ /[A-Z]/ || $nid =~ /%/; $new = $new->clone if $new == $self; $new->nid(lc($nid)); return $new; } 1; Save