const regex = /^(?<protocol>[a-z\-]+)?:?(?<slash>\/\/)?(?<host>[a-zA-Z0-9\.]+)?(?P<port>:\d+)?$/gm;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('^(?<protocol>[a-z\\-]+)?:?(?<slash>\\\/\\\/)?(?<host>[a-zA-Z0-9\\.]+)?(?P<port>:\\d+)?$', 'gm')
const str = `https://example.domain
http://example.domain
//example.domain
//example.com
https://example.com:34
//example.com:23
example.com`;
// Reset `lastIndex` if this regex is defined globally
// regex.lastIndex = 0;
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