diff -r 266a7e9b9237 -r 6d3c3db11e72 uh_parser/XML/SAX/Exception.pm
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/uh_parser/XML/SAX/Exception.pm	Wed Mar 03 16:51:26 2010 +0000
@@ -0,0 +1,126 @@
+package XML::SAX::Exception;
+
+use strict;
+
+use overload '""' => "stringify",
+    'fallback' => 1;
+
+use vars qw/$StackTrace $VERSION/;
+$VERSION = '1.01';
+use Carp;
+
+$StackTrace = $ENV{XML_DEBUG} || 0;
+
+# Other exception classes:
+
+@XML::SAX::Exception::NotRecognized::ISA = ('XML::SAX::Exception');
+@XML::SAX::Exception::NotSupported::ISA = ('XML::SAX::Exception');
+@XML::SAX::Exception::Parse::ISA = ('XML::SAX::Exception');
+
+
+sub throw {
+    my $class = shift;
+    if (ref($class)) {
+        die $class;
+    }
+    die $class->new(@_);
+}
+
+sub new {
+    my $class = shift;
+    my %opts = @_;
+    confess "Invalid options: " . join(', ', keys %opts) unless exists $opts{Message};
+    
+    bless { ($StackTrace ? (StackTrace => stacktrace()) : ()), %opts },
+        $class;
+}
+
+sub stringify {
+    my $self = shift;
+    local $^W;
+    my $error;
+    if (exists $self->{LineNumber}) {
+        $error = $self->{Message} . " [Ln: " . $self->{LineNumber} . 
+                ", Col: " . $self->{ColumnNumber} . "]";
+    }
+    else {
+        $error = $self->{Message};
+    }
+    if ($StackTrace) {
+        $error .= stackstring($self->{StackTrace});
+    }
+    $error .= "\n";
+    return $error;
+}
+
+sub stacktrace {
+    my $i = 2;
+    my @fulltrace;
+    while (my @trace = caller($i++)) {
+        my %hash;
+        @hash{qw(Package Filename Line)} = @trace[0..2];
+        push @fulltrace, \%hash;
+    }
+    return \@fulltrace;
+}
+
+sub stackstring {
+    my $stacktrace = shift;
+    my $string = "\nFrom:\n";
+    foreach my $current (@$stacktrace) {
+        $string .= $current->{Filename} . " Line: " . $current->{Line} . "\n";
+    }
+    return $string;
+}
+
+1;
+
+__END__
+
+=head1 NAME
+
+XML::SAX::Exception - Exception classes for XML::SAX
+
+=head1 SYNOPSIS
+
+  throw XML::SAX::Exception::NotSupported(
+          Message => "The foo feature is not supported",
+          );
+
+=head1 DESCRIPTION
+
+This module is the base class for all SAX Exceptions, those defined in
+the spec as well as those that one may create for one's own SAX errors.
+
+There are three subclasses included, corresponding to those of the SAX
+spec:
+
+  XML::SAX::Exception::NotSupported
+  XML::SAX::Exception::NotRecognized
+  XML::SAX::Exception::Parse
+
+Use them wherever you want, and as much as possible when you encounter
+such errors. SAX is meant to use exceptions as much as possible to 
+flag problems.
+
+=head1 CREATING NEW EXCEPTION CLASSES
+
+All you need to do to create a new exception class is:
+
+  @XML::SAX::Exception::MyException::ISA = ('XML::SAX::Exception')
+
+The given package doesn't need to exist, it'll behave correctly this 
+way. If your exception refines an existing exception class, then you
+may also inherit from that instead of from the base class.
+
+=head1 THROWING EXCEPTIONS
+
+This is as simple as exemplified in the SYNOPSIS. In fact, there's 
+nothing more to know. All you have to do is:
+
+  throw XML::SAX::Exception::MyException( Message => 'Something went wrong' );
+
+and voila, you've thrown an exception which can be caught in an eval block.
+
+=cut
+