in reply to Making all nibble zero lower than the offset

#!/usr/bin/env perl
use strict;
use warnings;

my $data = 0b1111_1111_1111;

my $offset = 8;
my $nibble_mask = 0xF;

while  (not 1<<$offset-1 & $nibble_mask) {
    $data ^= $nibble_mask;
    $nibble_mask <<= 4;
}
$data = $data ^ $nibble_mask;

printf("%b\n",$data);

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Re^2: Making all nibble zero lower than the offset
by trippledubs (Deacon) on Nov 20, 2018 at 18:46 UTC
    How naive I was to loop through looking for something already given... 
    #!/usr/bin/env perl
use strict;
use warnings;

my $data = 0b1111_1111_1111;
my $offset = 5;

my $mask = hex 'F' x ($offset % 4 == 0 ? $offset / 4 : $offset / 4 + 1
+);

printf("%b\n",$data ^ $mask);

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