const regex = /(?<LanguageTag>(?<langtag>(?<language>(?:[a-z]{2,3}(?<extlang>(?:\-[a-z]{3}){0,3}))|[a-z]{4}|(?<subtag>[a-z]{5,8}))(?:\-(?<script>[a-z]{4}))?(?:\-(?<region>[a-z]{2}|[0-9]{3}))?(?:\-(?<variant>[0-9a-z]{5,8}|[0-9][0-9a-z]{3}))*(?:\-(?<extension>(?<singleton>[a-wy-z0-9])(?:\-[0-9a-z]{2,8})+))*)|(?<privateuse>[xX](?:\-[0-9a-z]{1,8})+)|(?<grandfathered>[a-z]{1,3}(?:\-[0-9a-z]{2,8}){1,2}))/gmi;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('(?<LanguageTag>(?<langtag>(?<language>(?:[a-z]{2,3}(?<extlang>(?:\\-[a-z]{3}){0,3}))|[a-z]{4}|(?<subtag>[a-z]{5,8}))(?:\\-(?<script>[a-z]{4}))?(?:\\-(?<region>[a-z]{2}|[0-9]{3}))?(?:\\-(?<variant>[0-9a-z]{5,8}|[0-9][0-9a-z]{3}))*(?:\\-(?<extension>(?<singleton>[a-wy-z0-9])(?:\\-[0-9a-z]{2,8})+))*)|(?<privateuse>[xX](?:\\-[0-9a-z]{1,8})+)|(?<grandfathered>[a-z]{1,3}(?:\\-[0-9a-z]{2,8}){1,2}))', 'gmi')
const str = ``;
let m;
while ((m = regex.exec(str)) !== null) {
// This is necessary to avoid infinite loops with zero-width matches
if (m.index === regex.lastIndex) {
regex.lastIndex++;
}
// The result can be accessed through the `m`-variable.
m.forEach((match, groupIndex) => {
console.log(`Found match, group ${groupIndex}: ${match}`);
});
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions