Yes, thank goodness for Test262. One implements JS-compliant regexps by doing the natural thing, and then making Test262 pass. Some things have indeed improved

Yes, thank goodness for Test262. One implements JS-compliant regexps by doing the natural thing, and then making Test262 pass. Some things have indeed improved. The 'u' flag introduced in ES6 provides a much cleaner grammar for example. However the process is still busted. Here is a concrete example. /{1}/ is permitted by the ES6 spec (including Annex B). But in practice, "web browsers" rejected it. Rather than fixing the browsers, the spec was changed in ES8 to reflect "web-reality". https://github.com/tc39/ecma262/pull/303 https://github.com/tc39/ecma262/pull/303 Browsers could have become ES6 compliant here, with zero compatibility risk. But when there is non-compliance, it is the spec that moves.