Parallel Install

[Jesse Phillips]

One of the things I think dmd v1 and v2 should do is make it easier to 
both versions on the same computer. gcc lets you do this and is used very 
often especially when it comes to using kernel headers. I do not think 
that the current state of dmd needs such an ability, but I see it will be 
good for when it is used more and dmd v2 is finally released.

At this time I have successfully been able to install any number of dmd 
versions to my Debian system. There was not much work involved as it only 
required a few name changes. The dmd executable had the version number 
appended to it, along with libphobos.a. It also required having a the 
source code for phobos in a correctly version-ed directory. The main 
problem with this was the switching of which compiler version I was 
using. If I want to run dmd2.010 I would need to make sure that dmd.conf 
pointed to the correct phobos directory.

Since I believe that there is no reason v1.015 can't use v1.023's 
libphobos.a and the phobos source, I think it would be great if dmd was 
packages where dmd was named with its version (dmd1.023) and that 
libphobos/phobos source would have the major version added (libphobos1.a/
phobos1). And the last thing would be to have dmd.conf expanded to allow 
for specifying the Environment related to the version.

I think that this will be a good practice as use of D increases. I 
realize that after v2 is released, v1 is not getting support. However, 
projects made for v1 will not compile in v2, and it is likely older 
projects that are either complete or dead will not be updated. This could 
be true in business where an older program was developed in an older 
build, but newer software is being done in the latest stable build. There 
is also the fun factor, development is done in the stable release and 
then the beta/alpha builds are just there to try it and get familiar.