RegExp.prototype.flags
The flags property returns a string consisting of the flags of the current regular expression object.
Property attributes of RegExp.prototype.flags | 
    |
|---|---|
| Writable | no | 
| Enumerable | no | 
| Configurable | yes | 
Description
Flags in the flags property are sorted alphabetically (from left to right, e.g. "gimsuy").
Examples
Using flags
/foo/ig.flags;   // "gi"
/bar/myu.flags;  // "muy"
Polyfill
if (RegExp.prototype.flags === undefined) {
  Object.defineProperty(RegExp.prototype, 'flags', {
    configurable: true,
    get: function() {
      return this.toString().match(/[gimsuy]*$/)[0];
    }
  });
}
Specifications
| Specification | 
|---|
| ECMAScript Language Specification  # sec-get-regexp.prototype.flags  | 
Browser compatibility
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