How to use the snapdragon-util.hasType function in snapdragon-util

return function(node, nodes, i) {
    var opts = extend({}, this.options, options);
    var replaceRe = /(?:lang(uage)?|highlight|source|brush:\s*)[-]?| /g;
    var testRe = /(?:lang(uage)?|highlight|source|brush:\s*)/;

    var pre = opts.literalPre || !util.hasType(node, 'code');
    if (pre) {
      node.lang = (node.attr && node.attr['data-lang']) || '';
      var attribs = node.attribs;

      if (!node.lang && attribs && attribs.class) {
        var cls = attribs.class;
        if (cls && testRe.test(cls)) {
          node.lang = cls.replace(replaceRe, '');
        }
      }

      var parent = node.parent || {};
      if (!node.lang && parent && parent.attribs) {
        cls = parent.attribs.class;
        if (cls && testRe.test(cls)) {
          node.lang = cls.replace(replaceRe, '');

function tableize(ast) {
  util.visit(ast, {recurse: true}, function(node) {
    if (node.type === 'text') {
      node.val = node.val.trim();
    }
    return node;
  });

  if (!util.hasType(ast, 'thead')) {
    createHead(ast);
  }

  combineRows(ast);
  if (!util.hasType(ast, 'tbody')) {
    createBody(ast);
  }
  if (util.hasType(ast, 'tfoot')) {
    tfootNodes(ast);
  }

  util.mapVisit(ast, {recurse: true}, function(node) {
    if (node.type === 'br') {
      node.type = 'text';
      node.val = '';
    }
  });
}

util.visit(ast, {recurse: true}, function(node) {
    if (node.type === 'text') {
      node.val = node.val.trim();
    }
    return node;
  });

  if (!util.hasType(ast, 'thead')) {
    createHead(ast);
  }

  combineRows(ast);
  if (!util.hasType(ast, 'tbody')) {
    createBody(ast);
  }
  if (util.hasType(ast, 'tfoot')) {
    tfootNodes(ast);
  }

  util.mapVisit(ast, {recurse: true}, function(node) {
    if (node.type === 'br') {
      node.type = 'text';
      node.val = '';
    }
  });
}

if (ast.nodes.length === 3) {
    var text = { type: 'text', val: '' };
    var th = { type: 'th', attribs: { align: 'center'}, nodes: [text] };
    define(text, 'parent', th);
    define(th, 'parent', thead);
    thead.nodes.push(th);
    util.wrapNodes(th, Node);
    util.wrapNodes(thead, Node);
    ast.nodes.splice(1, 0, thead);
    return ast;
  }

  for (var i = 0; i < ast.nodes.length; i++) {
    var node = ast.nodes[i];
    if (node.nodes && util.hasType(node, 'th')) {
      define(node, 'parent', thead);
      thead.nodes.push(node);
      util.wrapNodes(thead, Node);
      ast.nodes[i] = thead;
      break;
    }
  }

  return ast;
}

function createBody(ast) {
  if (util.hasType(ast, 'tbody')) return;
  var open = ast.nodes.shift();
  var close = ast.nodes.pop();
  var started;
  var nodes = [];
  var tbody;

  var len = ast.nodes.length;
  var idx = -1;
  while (++idx < len) {
    var node = ast.nodes[idx];
    if (node.type === 'tr' && !started) {
      started = true;
      tbody = { type: 'tbody', nodes: [] };
      define(tbody, 'parent', ast);
      nodes.push(tbody);
    }

Node.prototype.hasType = function(type) {
  return utils.hasType(this, type);
};