Re: [boost] [MPL] A Proposal

Subject: Re: [boost] [MPL] A Proposal
From: Soul Studios (matt_at_[hidden])
Date: 2016-03-01 17:06:32

> My proposal is to make Metal officially into a new revision of Boost.MPL's
> API, essentially MPL2 as the original proposal by Robert Ramey put it,
> merging both into one single TMP library. The idea would be to provide a
> thin proxy for the current Boost.MPL API which would have two backends
> configurable by preprocessor switches: the original implementation and a
> another one based on Metal. This way older code using Boost.MPL could see
> immediate gains on performance by selecting the newer backend on supported
> compilers, while at the same time legacy code maintained on older compilers
> could still rely on Boost.MPL's impressive ability to run virtually
> anywhere. On the other hand, newer projects interested on pure type
> computations would have the newer API entirely available to them.

I see no problem with this proposal, provided that the preprocessor 
switches in question are the boost.config compiler trait macros. This is 
essentially what ends up happening with various libraries at a more 
in-depth level anyway, and as long as the syntax, as you say, is 
transparent, it doesn't matter either way.