Re: [boost] [cmake] Pull request announcement

Subject: Re: [boost] [cmake] Pull request announcement
From: Stefan Seefeld (stefan_at_[hidden])
Date: 2018-09-26 21:20:14

On 2018-09-26 05:02 PM, Raffi Enficiaud via Boost wrote:

>
> Sure, but you do not see the dependency graph in its full extent, and 
> this is a good thing: you want to see your direct dependencies, 
> because those are the ones that you directly manage.

Right.

>
> As soon as you (or any tool) start unrolling the chains of 
> dependencies, it may becomes messy. By taking the previous examples -- 
> very simple I have to say -- you may not even be aware of the 2nd copy 
> of library "Z".

To avoid to get into grid-lock in the discussion (similar to Peter's 
argument) I'm assuming that each library manages its own dependencies, 
and "installing a library" will imply resolving them. And indeed, if you 
install any Boost library (apt-get, dnf, vcpkg, ...) these dependencies 
will have been taken care of by some upstream package manager. So let's 
consider this a resolved issue.

>> All I want is the ability to work on a Boost library project, 
>> compiling it against some other prerequisite (versioned) libraries, 
>> some of which may be part of Boost.
>
> Yes, I understand.
>
> Do you mind having the ones that are part of boost - but only the ones 
> you need for working on your library - checked out/cloned on request?

I do. That's precisely the difference between your second use-case and 
the one I added, and I have explained what additional situation that 
would cover that aren't covered by the earlier ones.

[...]
> What I was saying before is the following. If I know that libX depends 
> on libY, I can make it such that by cloning or setting up libX, I 
> would like to get libY automatically.

Yes, I understand. I think that's a fine use-case to support, but it 
shouldn't be the only one.

> If I need external libraries, I can specify them explicitly from the 
> command line, or use facilities such as the cmake's find_package to 
> get them from the OS or any other location.
>
> I am fine with:
>
> cmake -DLIB_GIL=ON -DLIB_JPEG_LOCATION=/some/path/on/disk

Yeah, and that's all I'm asking, only that rather than libjpeg I'd also 
like to be able to find Boost dependencies (e.g., filesystem, core, 
etc.) that way.

Stefan

--
       ...ich hab' noch einen Koffer in Berlin...