Sorry, used to google groups, where reply is implicitly reply-all. Here's my response to Charles:
---------- Forwarded message ---------- From: Kris Kowal <[email protected]> Date: Wed, Sep 30, 2009 at 12:45 PM Subject: Re: Hermetic Evaluation, Modules Strawman To: Charles Jolley <[email protected]> On Wed, Sep 30, 2009 at 10:20 AM, Charles Jolley <[email protected]> wrote: > You can tell me why this module design relies on eval'ing a string? It > would be nice to be able to pass a Function object also. > > I wonder if that might be better for performance also as an optimized > implementation could potentially avoid re-parsing the JS. [Note: I haven't > implemented this kind of code before so there might not be any gains to be > had here...] > > I'm thinking of a case where you have a large-ish module where the cost of > eval'ing is non-trivial. Absolutely. The idea is that the proposed new eval.Module(names, text) case would be analogous to a Function(names..., text) constructor, which would give the implementation an opportunity to compile the program, sharing the AST or byte code between invocations of the Module. However, the purpose is definitely to transform text into a reusable component. The same purpose could potentially be achieved by "reparenting" a function declaration, such that the closure's parent scope reference is the hermetic, deeply frozen, primordial scope, but that would break lexical analysis in odd ways. Free variables in the function would become reference errors at call time. Kris Kowal _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
