John Maddock-3 wrote
I agree, the library should be able to decide whether expression templates should be an improvement or not.
A minor change in the library, defaulting the ExpressionTemplates
parameter
to a trait depending on the backend could help to that. The library could default to something reasonable, while the backend developer could always provide a specialization.
That would certainly be easy to do, but:
* That wouldn't help for types like cpp_int where the best strategy may depend on the runtime size of the number.
The backend developer could define the trait depending on the compile-time size. For run-time size the library set use a default, and it will be up to the user to force or not the use of expression templates.
* How would this differ in practice from the use of the typedefs we already provide where we know that expression templates don't help (mp_intXXX_t etc)?
Well, you will not have specific typedefs for all the sizes, so a way to associate the default value will be convenient. Vicente -- View this message in context: http://boost.2283326.n4.nabble.com/Multiprecision-Benchmarking-tp4631293p463... Sent from the Boost - Dev mailing list archive at Nabble.com.