Subj : Properties not defined with JS_DefineProperty possible?
To   : netscape.public.mozilla.jseng
From : Thomas Sondergaard
Date : Sat Jan 08 2005 07:03 pm

I'd like to use Spidermonkey as a glorified expression evaluator in a C++
application. I already have the values that needs to be available for the
expression evaluator available in a std::map<string, string>. I'd like to
make the keys in the map<string, string> available as global properties
with values corresponding to the values in the map. I am
wondering if there is a way that SpiderMonkey can dynamically look up
properties not defined with JS_DefineProperty? Otherwise I have to refresh
the defined properties to coincide with the keys available in the map
before I evaluate a script (or implement another scheme to keep the global
objects defined properties in sync with the keys in the map<string,string>) 

Many dynamic languages choose to invoke a special method on the object if
the desired method (or property) doesn't exist, e.g. method_missing in
ruby, __getattr__ in python, unknown in Tcl. I don't think such a method
exists in JavaScript, but it might exist in SpiderMonkey behind the scenes
to make it simple to support native objects where the available properties
change dynamically.

Best regards,

Thomas

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