- From: Boris Zbarsky <bzbarsky@MIT.EDU>
- Date: Tue, 11 Jun 2013 23:42:28 -0400
- To: Rik Cabanier <cabanier@gmail.com>
- CC: "public-script-coord@w3.org" <public-script-coord@w3.org>
On 6/11/13 11:28 PM, Rik Cabanier wrote:
> You've told me that dictionary members are optional by default [1]. Why
> does their IDL have '?' for most entries? Isn't that implied since every
> entry is optional anyway?
Consider these two dictionaries:
dictionary Foo1 {
DOMString member;
};
dictionary Foo2 {
DOMString? member;
};
and this object being converted to those dictionary types: { member:
undefined }.
Foo1 will produce { member: "undefined" } while Foo2 will produce {
member: null }.
Similarly, for { member: null }, Foo1 will produce { member: "null" }
while Foo2 will produce { member: null }.
This has nothing to do with the fact that having "member" is optional;
that just affects what happens when an object that does not have a
"member" property is involved.
-Boris
Received on Wednesday, 12 June 2013 03:42:58 UTC