use XML::Xalan;
my $tr = new XML::Xalan::Transformer;
# parse an XML string:
my $parsed = $tr->parse_string(<<"XML");
Hello
XML
# compile a stylesheet string:
my $compiled = $tr->compile_stylesheet_string(<<"XSLT");
XSLT
my $res = $tr->transform_to_data($parsed, $compiled);