On Nov 2, Paul Johnson said: >> can be called a closure. I feel that "closure" refers more to the action, >> and less to the means -- we are creating a subroutine (named or unnamed >> makes no difference) which holds on to variables that "should" be gone.
First, I have to thank you for taking the effort you just did. It's nice to see it. >1. The current documentation refers to closures as anonymous > subroutines. It doesn't state that named subroutines can not be > closures, but it does always state that closures are anonymous > subroutines, if it makes any distinction. Right. I happen to disagree with it. :) >2. Damian Conway's excellent "Object Oriented Perl" explicitly states > that named subroutines can be closures. And so does The Damian. (And the Randal, for that matter.) >3. Currently, Perl exhibits some surprising behaviour in certain > situations when a named subroutine is being used as a closure. In > practice, Perl does not properly close named subroutines. Most > people holding an opinion consider this a bug, although there is not > general consensus, and it is difficult to fix anyway. There are no > such caveats when using anonymous subroutines as closures. What are the problems with named subroutines being used as closures? Could you provide some test cases? >4. Ideally, I would like to see both Perl and its documentation patched > such that named subroutines can be safely used as closures. There > are probably but a handful of people capable of doing that, and so > far it has not been done. We'll see. -- Jeff "japhy" Pinyan [EMAIL PROTECTED] http://www.pobox.com/~japhy/ RPI Acacia brother #734 http://www.perlmonks.org/ http://www.cpan.org/ ** Look for "Regular Expressions in Perl" published by Manning, in 2002 ** -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
