Fwd: [WebIDL] platofmr array objects

Please use public-script-coord for all Web IDL discussions.

-------- Original Message --------
Subject: 	[WebIDL] platofmr array objects
Resent-Date: 	Wed, 13 Jul 2011 11:58:24 +0000
Resent-From: 	<public-webapps@w3.org>
Date: 	Wed, 13 Jul 2011 12:45:43 +0100
From: 	ext Andrew Oakley <andrew@ado.is-a-geek.net>
To: 	<public-webapps@w3.org>



http://dev.w3.org/2006/webapi/WebIDL/#es-array:
>  Platform array objects defy being fixed; if Object.freeze,
>  Object.seal or Object.preventExtensions is called on one, the
>  function MUST throw a TypeError.

Can I ask why?  I don't see any reason for this and it feels like it
would make implementations more complicated.  (This also seems to be
present in the platform objects description.)

§ 4.2.20.1 Platform array object [[GetOwnProperty]] method says that the
property descriptor for "length" whould have [[Configurable]] set to
true.  Later on we try to make sure it can't be deleted (§ 4.2.20.3).
Would it not be easier just to make it not [[Configurable]]?

The [[GetOwnProperty]] implementation also tries calling the normal
version of [[GetOwnProperty]] at the end of the algorithm rather than at
the start like Array and Arguments objects.  I could agree with it being
either way round, but it would be nice to be consistent with the
ECMAScript spec.

Finally, we don't define what "Reject" means here (although we do define
it for the "platform object" algorithms.

-- 
Andrew Oakley

Received on Wednesday, 13 July 2011 14:04:27 UTC