my $string = "aXbcXdefgXhijXklmnopqrXstuvwXyz";
my $target = 'X';

my @offsets;
while ( $string =~ /$target/g ) {
  push @offsets, pos($string) - length($target);
}

print "@offsets\n";

[download]

Does the trick for me, and it scales to arbitrary substrings.


(Update: hoisting length($target) out of the loop is a no-brainer. Alas, I had no brain at the time.)

In reply to Re: Producing a list of offsets efficiently by dws
in thread Producing a list of offsets efficiently by BrowserUk

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