DMD Source Archive - Why?

[Walter Bright]

We certainly could do more with .sar files, we just have to start somewhere.

If we're going to add features to a .tar file, like an index, aren't we then 
creating our own format and won't be able to use existing .tar programs?

Yes, one can skip through a .tar archive indexing as one goes. The problem is 
one winds up reading the .tar archive. With the .sar format, the index is at the 
beginning and none of the rest of the file is read in, unless actually needed. 
.tar is the only archive format I'm aware of that does not have an index 
section, and that's because it's designed for append-only magtapes. (Talk about 
ancient obsolete technology!)

Many archive formats also include optional compression, and various compression 
methods at that. All that support would have to be added to the compiler, as 
otherwise I'll get the bug reports "dmd failed with my .zip file!"

Still, the concept of presenting things as a single file is completely distinct 
from the file format used. The archive format being pluggable is certainly an 
option.