Calling toString on function proxy throws TypeError exception

Mark S. Miller erights at
Thu Oct 22 18:43:26 UTC 2015

I know that's true in general. But we made a few exceptions, especially for
functions and arrays. I thought F.p.toString was one, but maybe not. I just
don't remember.

On Thu, Oct 22, 2015 at 2:36 PM, Allen Wirfs-Brock <allen at>

> On Oct 22, 2015, at 11:23 AM, Mark S. Miller <erights at> wrote:
> Tom, this doesn't sound right to me. Didn't we intend Function.prototype.toString
> to be transparent thru function proxies?
> cc'ing Allen and Brian
> There is nothing unique to `toString` going on there.  This is just the
> problem that the default proxy handlers are not transparent across method
> calls in that they pass the proxy object rather than the target object as
> the `this` value to function that they ultimately invoke.  If that method
> needs to access internal slots of its `this` value or has `this` identify
> dependencies they don’t work.  It turns out that most Function.prototype
> methods have such dependencies.
> Allen

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