Re: undefined values in dictionaries from Cameron McCormack on 2013-06-23 (public-script-coord@w3.org from April to June 2013)

From: Cameron McCormack <cam@mcc.id.au>
Date: Mon, 24 Jun 2013 08:47:53 +1000
To: Boris Zbarsky <bzbarsky@MIT.EDU>
CC: "Tab Atkins Jr." <jackalmage@gmail.com>, Jonas Sicking <jonas@sicking.cc>, "public-script-coord@w3.org" <public-script-coord@w3.org>
Message-ID: <51C77B19.9040602@mcc.id.au>

Boris Zbarsky wrote:
> There are two issues here:
>
> 1) The new text has Type(V) where it means Type(value).
> 2) The [[Get]] is happening before we check for whether V is undefined
> or null (this problem was actually preexisting, but with
> [[HasProperty]]).
>
> What Gecko's code for this looks like is more like this (after making a
> change to align with the intent of the spec here):
>
> If Type(V) is Null or Undefined set value to Undefined. Otherwise let
> value be the result of calling the [[Get]] internal method on V
> with property name key.
> Let present be false if Type(value) is Undefined and true otherwise.

Thanks, fixed now.

Received on Sunday, 23 June 2013 22:51:31 UTC