<document source="test data">
    <comment xml:space="preserve">
        Tests many of the global variables defined within a perl directive
    <system_message level="1" line="3" source="test data" type="INFO">
        <paragraph>
            No directive entry for "perl" in module "Text::Restructured::Directive".
            Trying "perl" as canonical directive name.
    <paragraph>
        SOURCE = test data
    <paragraph>
        LINENO = 4
    <paragraph>
        DIRECTIVE = .. perl:: "DIRECTIVE = $DIRECTIVE"
    <paragraph>
        SUBSTITUTION =
    <substitution_definition names="subst-name">
        SUBSTITUTION = subst-name
    <paragraph>
        INCLUDES =
    <paragraph>
        TOP_FILE = perl17.rst