From: "Suraj N. Kurapati" <skurapat@...>
Date: 2006-06-11T05:39:50+09:00
Subject: Re: limiting Ruby Numbers

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Guest wrote:
> is there any ways to limit ruby numbers up to certain bytes? all i've
> read is that ruby numbers are limited to host's free memory

Use a bit mask to truncate the integer:

irb(main):011:0> ((2 ** 32) - 1)
=> 4294967295
irb(main):012:0> ((2 ** 32) - 1) & 0xFF
=> 255
irb(main):013:0> ((2 ** 32) - 1) & 0xFFFF
=> 65535
irb(main):014:0> ((2 ** 32) - 1) & 0xFFFFFF
=> 16777215
irb(main):015:0> ((2 ** 32) - 1) & 0xFFFFFFFF
=> 4294967295

For negative integers, be sure to preserve the sign by converting
the result back into two's complement form:

irb(main):021:0> -1
=> -1
irb(main):022:0> -1 & 0xFF
=> 255
irb(main):023:0> ~(-1 & 0xFF) + 1
=> -255

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