On Dec 7, 2007 11:00 AM, P T Withington <[EMAIL PROTECTED]> wrote: > My Lisp experience is that the compiler can warn when an > 'indefinite extent' (upward) closure is being created to help the > programmer avoid those (and the compiler can stack-allocate the > captured state for 'dynamic extent' (downward) ones). Some languages > eschew closures altogether because they are isomorphic to instances, > but with explicit allocation. Personally, I find downward closures a > powerful structuring tool, so I am glad we have them; but upward > closures can be difficult for even the expert to spot, so I hope > implementors will give us a hand there.
Upward closures, if I understand the terminology correctly, are quite common on the web, such as when passed as an argument to setTimeout or installed as an event handler. Doing a better job of handling the structuring uses of downward closures would indeed be quite righteous, but I don't think we're going to stamp out upward closures any time soon. Mike _______________________________________________ Es4-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es4-discuss
