What is the compilation model of D?

[David Piepgrass]

> I find it shocking that anyone would consider 15 seconds slow 
> to compile for a
> large program. Yes, D's builds are lightning fast in general, 
> and 15 seconds
> is probably a longer build, but calling 15 seconds 
> "slow-to-compile" just
> about blows my mind. 15 seconds for a large program is _fast_. 
> If anyone
> complains about a large program taking 15 seconds to build, 
> then they're just
> plain spoiled or naive. I've dealt with _Java_ apps which took 
> in the realm of
> 10 minutes to compile, let alone C++ apps which take _hours_ to 
> compile. 15
> seconds is a godsend.

I agree with Andrej, 15 seconds *is* slow for a edit-compile-run 
cycle, although it might be understandable when editing code that 
uses a lot of CTFE and static foreach and reinstantiates 
templates with a crapton of different arguments.

I am neither spoiled nor naive to think it can be done in under 
15 seconds. Fully rebuilding all my C# code takes less than 10 
seconds (okay, not a big program, but several smaller programs).

Plus, it isn't just build times that concern me. In C# I'm used 
to having an IDE that immediately understands what I have typed, 
giving me error messages and keeping metadata about the program 
up-to-date within 2 seconds. I can edit a class definition in 
file A and get code completion for it in file B, 2 seconds later. 
I don't expect the IDE can ever do that if the compiler can't do 
a debug build in a similar timeframe.