Subj : Re: Property resolution
To   : Thomas Sondergaard
From : Brendan Eich
Date : Sat Jul 30 2005 12:00 pm

Thomas Sondergaard wrote:
> Does spidermonkey maintain a map of properties even if I provide 
> setter/getter functions in my JSClass? I can see that my setter/getters 
> get called but even if they do nothing but return JS_TRUE the property 
> is set.


If you implement JSClass hooks, you are using generic property mapping 
and property value (slot) storage machinery in SpiderMonkey.

If you want no such generic value storage, use JSPROP_SHARED among the 
property's attributes.

If you want to manage your own mapping from id in an object to value, 
attributes, getter/setter, and other property fields, you will have to 
implement JSObjectOps yourself.  This is not recommended.


> How are properties resolved when setting and getting them?


What do you mean by resolved?  If you mean looked up, as in 
[[HasProperty]] in ECMA-262, then for properties of native objects (ones 
where you specialize at the JSClass layer), properties are looked up by 
high-level (JSObjectOps layer) get and set operations implemented in 
jsobj.c (js_GetProperty, js_SetProperty; these call js_LookupProperty).

/be

.