in reply to Incrementing only the masked bits

Here's an incrementing solution, inspired by tye's (but not simply doing the decrement and then subtracting from $mask, which would also work). 
my ($val, $mask) = (-1, 0x01000007);
     
do {
    $val += ~$mask+1;
    $val &= $mask;
    printf "0x%08.8x\n", $val;
} while ($val < $mask);

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Re^2: Incrementing only the masked bits (chicken eggs)
by tye (Sage) on Nov 10, 2005 at 20:18 UTC

    My version actually started out in my head closer to: 

    my $mask= 0x0f000007;
my $val= 0;
do {
    printf "0x%08.8x\n", $val & $mask;
    $val |= ~$mask;
    ++$val;
} while( $val <= ~0 );

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    but in typing it I decided to simplify. (:

    - tye        

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