[boost] Re: Big integer library

From: David Abrahams (dave_at_[hidden])
Date: 2004-04-30 15:25:18

Christoph Ludwig <cludwig_at_[hidden]> writes:

> Hi,
>
> On Fri, Apr 30, 2004 at 12:01:01PM +0200, Richard Peters wrote:
>> From: "Christoph Ludwig" <cludwig_at_[hidden]>
>> > > There is not much special about my library. Like the gmp, this library
>> uses
>> > > expression templates to avoid the creation of temporary values, which
>> when
>> > > the values become large provide an increase in performance.
>> >
>> > I sometimes wonder whether a bigint library that implements move
>> > semantics could not provide an additional significant efficiency
>> > gain. (Since I can avoid temporaries most of the time, my applications
>> > don't profit from expression templates that much.) I never performed
>> > experiments, though, this is only a conjecture.
>> >
>> > Do you have any plans in this direction?
>> 
>> What would implementing move semantics look like? Do you mean that an
>> expression like x = y * z where y and z aren't used after this expression
>> can be implemented as a swap(x, y); x *= z? I'm not sure how to implement
>> it, but if a method exists which provides a significant efficiency gain and
>> does not interfere with the interface too much, then I'm certainly
>> interested in implementing it.
>
> The only proposal I ever toyed with was Andrei Alexandrescu's
> Mojo. But recently there were threads about two proposals by David
> Abrahams and Andrea Torsello (search the archive for subjects that
> contain "move semantics").

And look in the boost sandbox at libs/move/test/*.

-- 
Dave Abrahams
Boost Consulting
http://www.boost-consulting.com