Re: Create a new native object with a constructor

On Sun, 2016-06-19 at 21:19 -0400, Boris Zbarsky wrote:
> On 6/19/16 9:05 PM, Braden McDaniel wrote:
> > What's the modern way to create a new native object that has a
> > constructor?
> 
> Has a constructor in what sense?  Do you mean that there is a
> JSNative 
> constructor that you want to get called that creates the object?

This.  That is, the JSClass::constructor member for the JSClass that
defines the native object implementation is not null.

> >     The preferred alternative is to save a copy of the constructor
> >     function for the class, then to call it using JS_New.
> > 
> > But that doesn't look like the right answer for a natively
> > implemented
> > object (since JS_NewObject still does look like part of the answer
> > for
> > natively implemented objects).
> 
> This comes back to my question above.  If the constructor JSNative 
> creates the object, then just calling it via JS_New will do the
> right 
> thing; it'll do the JS_NewObject itself.

Ah, got it.  Thanks.

On a related note, the JS_InitClass documentation includes this:

    If you provide a constructor for the class, then you should also
    pass an object to parent_proto. JS_InitClass uses parent_proto to
    build a prototype object for the class. The prototype object
    inherits properties and methods from the parent_proto object you
    provide.

I gather, then, that passing null for parent_proto is insufficient even
if the parent is Object? Is there some convenient way to get the proto
for Object in order to pass it here?

-- 
Braden McDaniel <[email protected]>
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