var options = { attributes: { rel: 'nofollow', title: 'Click for more information', }, className: 'internal-link', format: { url: function (value) { return value } }, ignoreTags: ['a'], validate: { url: function (value) { return value; } } }; var str = 'Map of the State of New-York Showing its Water and Rail Road Lines. Jan 1855, by direction of John T. Clark State Engineer & Surveyor.'; document.write(linkifyHtml(str, options));