const regex = /^(([^f]|f([^io]|o([^r]|r[a-z])|i([^ln]|l([^e]|e[a-z])|n([^d]|d[a-z]))))[a-z]*|(f(o|i|i(l|n))))?$/;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('^(([^f]|f([^io]|o([^r]|r[a-z])|i([^ln]|l([^e]|e[a-z])|n([^d]|d[a-z]))))[a-z]*|(f(o|i|i(l|n))))?$', '')
const str = `fo`;
// Reset `lastIndex` if this regex is defined globally
// regex.lastIndex = 0;
let m;
if ((m = regex.exec(str)) !== null) {
// 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