Number.prototype not being an instance breaks the web, too

Mark S. Miller erights at
Mon Apr 13 20:21:20 UTC 2015

On Mon, Apr 13, 2015 at 12:53 PM, Jordan Harband <ljharb at> wrote:

> Please note that the `@@toStringTag` changes mean that we do need to
> always have a Number.prototype method that throws when the value does not
> have a [[NumberData]] internal slot - I'm using `Number#toString` for that
> right now, but others may now be relying on the throw behavior of
> `Number#valueOf.

Wow, awesome catch!

Even though I recently implemented
, I completely missed that.

To see Caja's current set of dependencies:
They are:


If any of these stop throwing, for Caja and SES, that would be a breaking

Thanks for noticing this!

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