Actually, following up to my own reply: 3500 | 67 = 3567. So perhaps that sets your expectations for 3500 | -67.
But try -3500 | -67 for fun: it is -3 Bitwise or is no arithmetic and if you want to predict something about the resulting integers, you should know something about how they are stored. Negative integers are stored in 2-complement format: minus 1 is all bits set to 1. Turning bits off makes it a more negative number (as long as you don't touch the sign-bit) and turning more bits on makes it a smaller negative number. Doing bitwise-OR for the positive numbers 3500 and 67 results in 3567: proof that they don't have any overlapping bits. Know it turns out that 3500 and -67 have only overlapping bits: therefore the result is -67. (adding the bits from 3500 to the bits of -67 doesn't turn on any extra bits). Use bit operators to manipulate bits, and think of the operands as sets of bits. Bitwise OR is the union of 2 sets of bits. Don't think of the operands to bit operators as numbers, and don't try to do your sums using bitwise or! :-) --Tim -- http://mail.python.org/mailman/listinfo/python-list
