Calling toString on function proxy throws TypeError exception

Boris Zbarsky bzbarsky at
Tue Oct 27 13:18:23 UTC 2015

On 10/27/15 9:14 AM, Boris Zbarsky wrote:
> On 10/27/15 4:35 AM, Claude Pache wrote:
>> it is that, for any callable object, it will return a string and not
>> throw, because it was so since the dawn of JS.
> It's totally false for random "host objects" with a [[Call]] in ES5, per
> spec and in at least some implementations.  As you can tell in Firefox
> for example:
> (though it does not throw for document.all in Firefox, for interesting
> implementation reasons).

Though note that I would be just fine with defining 
Function.prototype.toString to return something akin to what it does for 
"host functions" for any "host object" with a [[Call]]...


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