Re: [boost] New dependency report

Subject: Re: [boost] New dependency report
From: Peter Dimov (lists_at_[hidden])
Date: 2014-06-07 21:12:26

Andrey Semashev wrote:

> What kind of changes do you think will be needed and not possible without 
> breaking compatibility?

I don't know enough to answer this question. MPL is somewhat complicated. 
It's not quite clear, from a brief look, which parts are essential and which 
parts are workarounds.

> I think, at first it will be simply enough to just move the components to 
> the new submodule.

Even that is going to not be as easy as it sounds. Look at 
boost/mpl/and.hpp, for example. And it's not clear whether, if we move a 
component into MPL.Core and remove all workarounds, this will not break 
components in MPL that depend on those workarounds for some reason.

In short, it looks like a nontrivial project. Maybe it's easier than it 
appears. I don't know.

> Yes, I probably made that statement overly confident. I'm not the 
> maintainer of MPL nor I have rights to create submodules, so I clearly 
> don't have the upper hand.

MPL doesn't have an official maintainer at the moment, I think. And creating 
a submodule is the least of our worries. I do have that right. That's not 
the issue at all. :-)

> However, I don't see tag dispatching in Core now and I'm not sure it will 
> appear (and need refactoring such as above) in the near future.

No, there isn't any tag dispatching in Core; the intent was to provide the 
infrastructure for tag dispatching to libraries that do tag dispatching and 
wish to avoid the dependency on MPL.