Robert Citek wrote:
>
> Hello all,
Hello,
> I want a variable to be memoized, that is, keep the variable available only
> to the function and the value remembered across invocations. So far, I
> have created two versions listed below, both of which "work." The first
> version prints a warning message 'Variable "$bar" will not stay shared ...'
> which I would like to avoid by coding The Right Way(TM). Also, I wonder if
> the second version is modular enough so that it can be put in a module and
> loaded.
>
> Is there a better way to memoize?
>
> ------
>
> #!/usr/bin/perl -wl
> # version 1
> use strict
>
> sub foo {
> my $bar=100;
> sub bat {
> $bar++;
> return $bar;
> }
> return bat();
> }
>
> print foo();
> print foo();
> print foo();
>
> ----------
>
> #!/usr/bin/perl -wl
> # version 2
> use strict
>
> BEGIN {
> my $bar=100;
> sub foo {
> $bar++;
> return $bar;
> }
> }
>
> print foo();
> print foo();
> print foo();
If you want memoize you can get the Memoize module:
http://search.cpan.org/author/MJD/Memoize-1.01/ but it looks like you
want a closure instead. All you need to do is limit the scope of the
variable so that only the sub can see it.
{ # limit scope of $bar
my $bar = 100;
sub foo { ++$bar }
}
John
--
use Perl;
program
fulfillment
--
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
