[WebIDL] Dictionary with attribute set to 'undefined' counts as set?

• From: Dirk Schulze <dschulze@adobe.com>
• Date: Sat, 14 Jun 2014 17:45:07 +0000
• To: "public-script-coord@w3.org" <public-script-coord@w3.org>
• Message-ID: <B662CE17-8593-4095-86D8-C05064BCA2F1@adobe.com>

Hi,

I have a question to dictionaries:

If I have a dictionary like this

	var dic = {x: 1, y: undefined, z: 1, w: 1};

and pass it as argument to DOMPoint: 

	new DOMPoint(dic);

How should the attribute value of DOMPoint.y look like?

Should it be:
a) 0 because dic.y doesn�t count as initialized and it take the default initial value of DOMPoint.y?
b) NaN because dic.y counts as initialized and undefined is transformed to NaN since the attribute value of y is of type Number?

The relevant spec is Geometry Interfaces. The relevant IDL looks like this:

dictionary DOMPointInit {
    unrestricted double x = 0;
    unrestricted double y = 0;
    unrestricted double z = 0;
    unrestricted double w = 1;
};

[Constructor(optional DOMPointInit point)]
interface DOMPoint : DOMPointReadOnly {
    inherit attribute unrestricted double x;
    inherit attribute unrestricted double y;
    inherit attribute unrestricted double z;
    inherit attribute unrestricted double w;
}

Greetings,
Dirk

Received on Saturday, 14 June 2014 17:45:40 UTC