For reference: https://bugs.ecmascript.org/show_bug.cgi?id=2546
`Array#copyWithin` has a (non-normative) signature of `(target, start, end = this.length)`. However, this is slightly misleading because the spec actually calls `ToLength` on `this.length` and then uses *that* for the default value of `end`. This changes `end`'s effective value when `this.length` is negative. In the bug we discuss changing the non-normative descriptive text to be less misleading. But I'd like to invite broader discussion on a different approach: can we change the spec so that the `end = this.length` default was actually correct? This would only possibly change behavior on array-likes with negative length, and probably wouldn't even change observable behavior in that case (since `length` is treated as 0). Basically we'd be just calling `ToInteger` on the default value of `end` rather than `ToLength`. But it would be an end-run around confusing language in the spec. --scott _______________________________________________ es-discuss mailing list es-discuss@mozilla.org https://mail.mozilla.org/listinfo/es-discuss
