David A. Greene wrote: > Aleksey Gurtovoy wrote: > > Figuring out a reasonable way to specify the promotion > > rules is probably the hardest part there... > > I actually did some work on this in the past but it's been sitting > on the shelf for a while and probably needs a bit of pounding into > shape. The design idea was to specify a template that acts as a > lookup table keyed on the two source types and returning the correct > result type according to a two other parameters: the operation > and a parameter I'll call the "ruleset." The ruleset can be used to > provide different promotion strategies such as ANSI/ISO C++ arithmetic > rules, "keep the most information" rules and so on. > > A good example of ruleset use is the use of the "most information" > rule to implement integer divide using double types to retain > precision. > > Does this sound at all interesting?
Very! > The implementation is complex (didn't have MPL at the time) but can > probably be cleaned up some. It may be too flexible for your needs. Even if so, it would give us some interesting prior art to start with (besides the Blitz++'s one). Aleksey _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost
