Here is a small code which I is not working as I expect:

use feature 'switch';
my $h = {s => 'ababa'};
$h->{s} =~ m/^/g;
while (1) {
  given ($h->{s}) {
    when(/a/g) { print pos $h->{s}, "\n" }
    default { exit }
  }
}

[download]

On my version of Perl (v5.14.2), I get:

0
0
0

[download]

But I expected:

1
3
5

[download]

The /g modifier to the regex obviously works because the loop stops after three iterations. So why does pos() fails to report the correct value ?

If I replace the given/when by an if statement then everything works fine.

Any helps understanding this will be appreciated (even more if I can get the value of pos()). Thanks!

In reply to Using pos() inside given/when by Anonymous Monk

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