----- Original Message ----- From: "Jeffrey Lee Hellrung, Jr." <jhellrung@ucla.edu> To: <boost@lists.boost.org> Sent: Wednesday, June 16, 2010 11:31 PM Subject: Re: [boost] [xint] Design Question
On 6/16/2010 2:30 PM, Chad Nelson wrote:
On 06/16/2010 02:31 PM, vicente.botet wrote:
The problem is: what should the library do if the user asks for an unsigned *non*-fixed-length integer? [...]
What about making the difference between two unsigned integers a signed integer?
That sounds like a useful behavior, but if the developer using the library says it should be an unsigned number, I don't think the library should override that.
I think Vicente probably had operator- in mind. Then you'd need signed <-> unsigned conversions, but I'd think that would be expected.
Yes, I expected signed <-> unsigned conversions, and an exception if the signed is < 0. The user can always test if the signed is <0 and do whatever s/he thinks is better for its application if s/he wants a unsigned value.
I don't think you should disable use of unsigned, arbitrary-length integers. +1
Best, Vicente