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Perl-Sensitive Sunglasses

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The wording does seem to imply that it would return a list of bit values, but that isn't what it is doing. Rather, that routine returns a list of bit positions that are set (have a 1 in them).

If you just want the list of bits, it is probably simplest to split an unpacked string.

my @bits = split //, unpack "b*", $vec;

To furthur demonstrate:

use integer; my $vec = 42; my @ints; my $bits = unpack "b*", $vec; my @bits = split //, unpack "b*", $vec; push @ints, 0 if $bits =~ s/^(\d)// && $1; push @ints, pos $bits while($bits =~ /1/g); print "\n"; print join ', ', @ints; print " <-- bit positions set\n"; print join ', ', @bits; print " <-- bits \n";
2, 4, 5, 9, 12, 13 <-- bit positions set

In reply to Re: Confusion about code sample in perlfaq4 by thundergnat
in thread Confusion about code sample in perlfaq4 by vr

and:  <code> code here </code>

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