RegExp.prototype.flags - JavaScript | MDN (original) (raw)
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The flags accessor property of RegExp instances returns the flags of this regular expression.
Try it
// Outputs RegExp flags in alphabetical order
console.log(/foo/gi.flags);
// Expected output: "gi"
console.log(/bar/muy.flags);
// Expected output: "muy"
Description
RegExp.prototype.flags has a string as its value. Flags in the flags property are sorted alphabetically (from left to right, e.g., "dgimsuvy"). It actually invokes the other flag accessors (hasIndices, global, etc.) one-by-one and concatenates the results.
All built-in functions read the flags property instead of reading individual flag accessors.
The set accessor of flags is undefined. You cannot change this property directly.
Examples
Using flags
/foo/ig.flags; // "gi"
/bar/myu.flags; // "muy"
Specifications
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-get-regexp.prototype.flags |