ldc and gdc

[Marco Leise]

Am 06.08.2011, 11:16 Uhr, schrieb Jacob Carlborg <doob at me.com>:

> On 2011-08-05 11:53, Marco Leise wrote:
>> I have noticed DVM around.
>> The situation on Gentoo is typically that when there are different
>> versions of the same package, that can be installed in different
>> 'slots'. A dependency of these packages is a control file for eselect, a
>> tool to switch between the currently active implementation (OpenJDK, Sun
>> Java, ...), package version (boost) and several other system
>> configuration options. 'python' for example ends up as a symlink to
>> either python2.7 or python3.1 and there are corresponding directory
>> names for the libraries. It would be ideal if dmd was a symlink to
>> either dmd1 or dmd2 and they would both use a separate dmd.conf. But
>> since the source code is available for a while now that should be easy
>> to make possible.
>> I have never used DVM, but I imagine it works like Maven or the Eclipse
>> updater. So it would download precompiled compilers and libraries into
>> the user's home directory, right? With Gentoo being a source
>> distribution it is usually avoided to download binaries from the
>> internet so I guess DVM would be one of two options to install D
>> compilers on Gentoo. The difference in usage would be like this for an
>> installation:
>> dvm: "dvm install 1.068"
>> portage: "emerge =dmd-1.068"
>> and this for setting the system-wide default compiler:
>> dvm use 1.068 -d
>> eselect dmd set dmd1
>> Granted, the portage version would only allow one dmd 1 compiler to be
>> installed at a time, but that is ok for most users. I guess in theory
>> there could even be slots for every single release of dmd. This is
>> already done for Boost and automake in practice (with major revisions).
>> OTOH there is no option to set the compiler for the current shell, but
>> maybe "export DMD=dmd1", "make posix.mak" should work.
>
> It seems like DVM and portage/eselect are similar. I think it's a huge  
> advantage to be able to have multiple versions of DMD installed. I use  
> both D1 and D2, (mostly D1). I also think it's especially useful when  
> there's almost always something that breaks in a new release of DMD.  
> Then you can easily go back to an older version if you need to.
>
> BTW, Nick Sabalausky is working on making it possible to install DMD  
> from github via DVM.

Even if this begins to sound childish, I have to add for completeness sake  
that in portage you have the version number 9999 to indicate a build from  
online source repositories. So dmd-9999 would be the Github version. The  
source tree is cloned into /usr/portage/distfiles/git-src/ and updated  
each time the package is being reinstalled. Additional tools like  
'smart-live-rebuild' have emerged to make rebuilding changed repositories  
easier.