Jenda Krynicky wrote:
> I believe they meant "goto &NAME". <illuminating example snipped> > This way perl doesn't create a new record in the call stack every > time you "call" the _fib(). > As you can see if you comment out the return in fib_() and remove > the comment from "croak ..." and "use Carp;". (die() with stack > print). > > See > perldoc -f goto Thanks :). That's great. I don't use goto much, except for a couple of very specific situations, so I hadn't read the docs for goto. It seems I missed a very interesting beast in goto &NAME. In fact , I sent a friend of mine some code recently that would have been improved in one place by its use. But I still have a question :). As I understand it when tail-call optimization is done automatically there are two advantages. One is that the stack doesn't grow out of control, so that you don't have to worry about blowing it up if you recurse very deeply. The other is that the overhead of successive calls is eliminated. In theory (but, I think, often not in practice) the optimized routine should be as efficient as the equivalent iterative routine. Using goto &name has the first advantage, but does it have the second? That is, does goto &NAME have the same overhead as a normal call? Does anyone write this kind of recursive function regularly? I mean, is it idiomatic in the more rarefied Perl circles? Or is it better (from a style point of view) to use iterative constructs even in places where recursion is more natural, but tail-call optimization would be required? Thanks Tagore Smith -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
