On Thu, Jan 12, 2012 at 1:40 AM, James Burke <jrbu...@gmail.com> wrote: > I did a blog post on AMD that also talks about harmony modules. In the > "ECMAScript" section I talk about some of the questions I have about > with harmony modules: > > http://tagneto.blogspot.com/2012/01/simplicity-and-javascript-modules.html
Thanks for writing this -- we appreciate the feedback. [As an aside, Dave and I still plan to address your point that module instance objects need to be usable as functions.] As to your current post, I think the fundamental disagreement is all encapsulated here: "ES harmony may be able to do something a bit different, but the basic mechanisms will be the same: get a handle on a piece of code via a string ID and export a value." First, there are two things you might mean by "piece of code". One is "the source code for a library/script", which is necessarily identified by a URL on the Web (perhaps by a filename in other contexts, like Node). That stays as a string in every design. The other is "a library that I know I have available", and that we're not using strings for. Instead, you refer to modules by name, just like variables are referred to by name in JS. Second, we don't want to just stop with "export a value". By allowing the module system to know something ahead of time about what names a module exports, and therefore what names another module imports, we enable everything from errors when a variable is mistyped to cross-module inlining by the VM. Static information about modules is also crucial to other, long-term, desires that at least some of us have, like macros. Third, the "basic mechanisms" available for existing JS module systems require the use of callbacks and the event loop for loading external modules. By building the system into the language, we can not only make life easier for programmers, we statically expose the dependencies to the browser, enabling prefetching -- here, the basic mechanisms don't have to be the same. -- sam th sa...@ccs.neu.edu _______________________________________________ es-discuss mailing list es-discuss@mozilla.org https://mail.mozilla.org/listinfo/es-discuss
