Subj : Re: Create an instance of a JS object from C
To   : spellcaster <spellcaster@web.de>
From : Brendan Eich <brendan@meer.net>
Date : Fri Dec 12 2003 09:55 am

spellcaster wrote:

>Hi!
>
>I'm pretty new to spidermonkey and I'm amazed fast I could integrate
>it into my app. I guess I'm just blind, but I can't find a function to
>create an instance of a Class within the context.
>  
>

By "context" at the end of that sentence, do you mean "scope" or "global 
object"?  I'm always vigilant to distinguish the two, since JSContext in 
the JS API is for execution, not scope.  You need one JSContext per 
thread concurrently executing JS or calling the API, but you might need 
more or fewer scope chains ending in one or more global objects.  
Consider the browser embedding, which appears to be single-threaded, but 
where each window, frame, or iframe is its own global object.

>Now I want to populate my context with some instances of Dummy
>objects. Right now what I do is something like this:
>
>-- Code --
>jsval rval;
>char* script = "test = new Dummy();";
>JS_EvaluateScript(
>    jsContext, jsGlobalObj, 
>    script, strlen(script), 
>    "[init]", __LINE__, 
>    &rval); 
>-- /Code --
>
>To ensure that a variable named "test" of type "Dummy" exists in the
>context.
>Is there a pure C way of doing this? Calling JS_EvaluateScript() seems
>hackish...
>

What about JS_NewObject, JS_ConstructObject, and 
JS_ConstructObjectWithArguments?  If you want to call JS_NewObject and 
then to define the resulting new object as the value of some named 
property in another object, use JS_DefineObject.

/be

.