Non-generic traps for non-generic objects (was: Overriding Map/etc with get/set hooks?)

Tom Van Cutsem at
Sat May 25 01:33:38 PDT 2013

2013/5/24 Tab Atkins Jr. <jackalmage at>

> The problem is that the Map#set method grabs an *internal property*,
> bypassing Proxies, etc., so you can't defend against it.

Just to clarify, grabbing internal properties doesn't bypass proxies, not
as currently specced.
That's why,k,v) failed in my example upstream
(where m is a proxy). The Map#set method will not bypass the proxy to reach
into the wrapped object's [[MapData]].

I think what you meant is that accessing an internal property doesn't
trigger any proxy traps, so you can't directly intercept it. That is true.

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