code: function _getHandler(nodeType, handlerObj) {
    if ({}.hasOwnProperty.call(handlerObj, nodeType)) {
      return handlerObj[nodeType];
    }
    return false;
  }
docs: Private: uses `nodeType` to determine which handler method should be used to
  parse a node.
  
  * `nodeType` {String} the `type` property of a {Node}.
  * `handlerObj` {Object} of {Function}s whose property names match {Node} `type`.
  
  Returns {Function} when the `nodeType` matches a `handlerObj` property.
  Returns {false} when no `nodeType` matches.