FWIW I tried feature state with no avail. (the idea was to return a tied iterator)

But this only works for the first initialization, test() is never called again

use strict;
use warnings;
use Data::Dump qw/pp dd/;
use feature 'state';

my $x = 0;
sub test { warn ++$x; return $x }

for my $a (1..3) {
    print "\n---\n";
    while (state $z = test() ) {
        print "$a:$z\n";
        last unless  $a--;
    }
}

[download]

1 at d:/Users/lanx/pm/state_loop.pl line 7.

---
1:1
0:1

---
2:1
1:1
0:1

---
3:1
2:1
1:1
0:1

[download]

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Wikisyntax for the Monastery

In reply to Re: Can I check if a loop's scope is entered for the first time? (state) by LanX
in thread Can I check if a loop's scope is entered for the first time? by LanX

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