function extractor( name ) {
	return attacher;

	/**
	* Attach a plugin to a remark processor in order to extract the specified section.
	*
	* @private
	* @returns {Function} transformer
	*/
	function attacher() {
		return transformer;
	}

	/**
	* Transforms a Markdown file.
	*
	* @private
	* @param {Node} ast - root node
	*/
	function transformer( ast ) {
		sectionNodes( ast, name );
	}
}
Returns a remark attacher that extracts the section with the given name.

@private
@param {string} name - section name
@returns {Function} remark attacher function