// it resumes reading the next one down.
type Stack struct {
	tr []TokenReader
}

// Push adds tr to the top (end) of the input stack. (Popping happens automatically.)
func (s *Stack) Push(tr TokenReader) {
	s.tr = append(s.tr, tr)
}

func (s *Stack) Next() ScanToken {
	tos := s.tr[len(s.tr)-1]
	tok := tos.Next()
	for tok == scanner.EOF && len(s.tr) > 1 {
		tos.Close()

        // <thead>
        //   <tr>
        //     <td>Property</td>
        //     <td>Description</td>
        //   </tr>
        // </thead>
        Element thead = document.createElement("thead");
        parent.appendChild(thead);
        Element tr = document.createElement("tr");
        thead.appendChild(tr);
        Element td = document.createElement("td");
        tr.appendChild(td);

        // <thead>
        //   <tr>
        //     <td>Method</td>
        //     <td>Description</td>
        //   </tr>
        // </thead>
        Element thead = document.createElement("thead");
        parent.appendChild(thead);
        Element tr = document.createElement("tr");
        thead.appendChild(tr);
        Element td = document.createElement("td");
        tr.appendChild(td);

                                    </tr>
                                    <tr>
                                        <th><la:message key="labels.urls"/></th>
                                        <td>${f:br(f:h(urls))}<la:hidden property="urls"/></td>
                                    </tr>
                                    <tr>

    void build(ClassDoc classDoc) {
        Element thead = getChild(classDoc.getPropertiesTable(), "thead");
        Element tr = getChild(thead, "tr");
        List<Element> header = children(tr, "td");
        if (header.size() < 1) {
            throw new RuntimeException(String.format("Expected at least 1 <td> in <thead>/<tr>, found: %s", header));
        }
        Map<String, Element> inheritedValueTitleMapping = new HashMap<String, Element>();

 * <tr><td><code>plugin.*</code></td>          <td></td>               <td></td></tr>
 * <tr><td><code>*</code></td>                 <td></td>               <td>user properties</td></tr>
 * <tr><td><code>*</code></td>                 <td></td>               <td>project properties</td></tr>
 * <tr><td><code>*</code></td>                 <td></td>               <td>system properties</td></tr>
 * </table>

        <table>
            <thead><tr><td>Name</td></tr></thead>
            <tr><td>block</td></tr>
            <tr><td>listBlock</td></tr>
            <tr><td>notBlock</td></tr>
        </table>
    </section>
    <section><title>Properties</title>
        <table>
            <thead><tr><td>Name</td></tr></thead>
            <tr><td>block</td></tr>
            <tr><td>listBlock</td></tr>
        </table>

        def content = parse('''<section>
                <section><title>Properties</title>
                    <table><thead><tr><td/></tr></thead></table>
                </section>
                <section><title>Methods</title>
                    <table><thead><tr><td/></tr></thead></table>
                </section>
            </section>
        ''')

        when:
        ClassDoc doc = withCategories {

 * </tr>
 * <tr>
 * <td>{@link DateFormat#FULL}の形式</td>
 * <td>{@literal yyyy'年'M'月'd'日' H'時'mm'分'ss'秒' z}</td>
 * </tr>
 * <tr>
 * <td rowspan="4">プレーン形式</td>
 * <td>{@link DateFormat#SHORT}の区切り文字を除去した形式</td>
 * <td>{@literal yyMMdd HHmm}</td>
 * </tr>
 * <tr>
 * <td>{@link DateFormat#MEDIUM}の区切り文字を除去した形式</td>
 * <td>{@literal yyyyMMdd HHmmss}</td>
 * </tr>
 * <tr>

	for {
		// Discard the remainder of the file and any padding.
		if err := discard(tr.r, tr.curr.physicalRemaining()); err != nil {
			return nil, err
		}
		if _, err := tryReadFull(tr.r, tr.blk[:tr.pad]); err != nil {
			return nil, err
		}
		tr.pad = 0

		hdr, rawHdr, err := tr.readHeader()
		if err != nil {
			return nil, err
		}
		if err := tr.handleRegularFile(hdr); err != nil {
			return nil, err
		}