On Mar 24, 2008, at 11:21 PM, Thomas Reilly wrote: > ... and all > that static information sure doesn't hurt when it comes to > performance (can I say that much Brendan? ;-)
If you've got it, use it -- no point in dropping type information during a source to bytecode or other transformation. Just don't expect the web to type-annotate the way Flash authors did (with some grumbling) based on the carrot of speed that you guys dangled. > Sometimes loosey > goosey is good, in large frameworks (and certainly OSes) not so > much. We think that one language can serve both ends. I'm pretty sure Mark wants to avoid loose geese too, but he has reached different conclusions. My goal is to work from conclusions backward to premises such as "ES4 is statically typed" and try to identify the reason for that kind of statement. This may not succeed. As Graydon once observed, a lot depends on "mood" of the language. People see static type checkers (even optional ones, as optional as JSLint) and type annotations (also optional), and the 'class' keyword (which is used in dynamic languages too), and suddenly it's a statically typed language and therefore b-a-d. The charge Matthias leveled about intentional loopholes (ES4's * type, which is the default annotation) meaning errors can (as is usual in ES3 today) originate from anywhere in a large system and mess over your hybrid or partially typed code is pretty much on target. But we are trying not to do Contract or TypeScheme research, and we are definitely not imposing a static type system (not even within new modules -- and defining a module is turning out to be quite hard in JS on the web). Contrary to all the claims alleging that we are doing those bad things. If ES4 users want to lock a module down in a static-typing sense, they can annotate all API entry points with non-like types (wrap would allow untyped client code to pass plain old objects and arrays, at a price). Further self-imposed B&D programming inside the module is optional in my view. This is the best that I believe we can do for ES4. It beats purely dynamic typing for any non-trivially-small codebase. I wish I had the option to code in this language when writing Narcissus. /be _______________________________________________ Es4-discuss mailing list Es4-discuss@mozilla.org https://mail.mozilla.org/listinfo/es4-discuss
