Re: [matrix][cssom-view] DOMPoint, DOMPointLiteral definitions

On Sat, 28 Sep 2013 00:08:35 +0200, Robert O'Callahan  
<robert@ocallahan.org> wrote:

> On Sat, Sep 28, 2013 at 10:07 AM, Robert O'Callahan  
> <robert@ocallahan.org>wrote:
>
>> -- DOMRect is the base interface for both immutable and mutable rects.  
>> It
>> defines "current x/y/width/height" state and can expose methods that use
>> that state. Other APIs can take DOMRects and be defined in terms of the
>> current state. It allows read-only access to the current state and does  
>> not
>> offer any mutation APIs.
>> -- DOMRectImmutable extends DOMRect and adds the invariant that the  
>> state
>> never changes. It probably doesn't need to add any new API. (However,  
>> being
>> immutable is potentially meaningful to clients, because it allows them  
>> to
>> avoid copying, so testing whether a rect is immutable could have value.)
>> -- DOMRectMutable extends DOMRect and adds APIs to mutate the rect.
>>
>
> BTW if we take this approach then a "live rect" that's not immutable but
> can't be changed by the client is exactly DOMRect.

Do we need to differentiate between live/read-only and immutable at all?

-- 
Simon Pieters
Opera Software