AST files instead of DI interface files for faster compilation and easier distribution

[Walter Bright]

On 6/18/2012 6:07 AM, Don Clugston wrote:
> On 17/06/12 00:37, Walter Bright wrote:
>> On 6/14/2012 1:03 AM, Don Clugston wrote:
>>>> It is for debug builds.
>>> Iain's data indicates that it's only a few % of the time taken on
>>> semantic1().
>>> Do you have data that shows otherwise?
>>
>> Nothing recent, it's mostly from my C++ compiler testing.
>
> But you argued in your blog that C++ parsing is inherently slow, and you've
> fixed those problems in the design of D.
> And as far as I can tell, you were extremely successful!
> Parsing in D is very, very fast.

Yeah, but I can't escape that lingering feeling that lexing is slow.

I was fairly disappointed that asynchronously reading the source files didn't 
have a measurable effect most of the time.