attributes not allowed on a interface?
On 22/04/2008, Eric Suen <eric.suen.tech at gmail.com> wrote:
Since attributes not allowed on a interface, for W3C Node interface:
interface Node { const unsigned short ELEMENT_NODE = 1; }
what is the same statement in EcmaScript 4? I don't see the point why static const attributes is not allowed on a interface?
Entirely based on my own understanding of how it works: Interfaces in ES4 are only nominal types and signatures, they do not carry implementation and thus no initialised values. Classes do that. So, the interface would define the properties, the class that implement that interface carry the initialisation of those properties.
For the DOM, it all gets a bit bad since the DOM requires multiple inheritance on the prototype chain if you want to implement a consistent interface object - prototype inheritance as can be seen in moz, saf and op but not in ie. In other words, the ES4 inheritance model does not allow you to implement the DOM interfaces compatibly with those three browsers strictly using native inheritance systems. You'd have to implement getters and settters á la the Bindings spec[1] to achieve that. Those getters and setters are IMO broken, because they don't ensure a property is looked up in a subtype before they are looked up in it's supertype[2].
[1] uri:http://www.w3.org/TR/DOM-Bindings/#interface-prototype-object [2] uri:http://lists.w3.org/Archives/Public/public-webapi/2008Apr/0091.html
Since attributes not allowed on a interface, for W3C Node interface:
interface Node { const unsigned short ELEMENT_NODE = 1; }
what is the same statement in EcmaScript 4? I don't see the point why static const attributes is not allowed on a interface?
Hi, Since attributes not allowed on a interface, for W3C Node interface: interface Node { const unsigned short ELEMENT_NODE = 1; } what is the same statement in EcmaScript 4? I don't see the point why static const attributes is not allowed on a interface? Regards Eric