DMD svn and contract inheritance

[Lutger]

Walter Bright wrote:

> Jason House wrote:
>> With small commits to dmd, it should be trivial to know what small
>> change in dmd caused a user observable change in behavior.
> 
> The problem is, one doesn't know if it is a problem with the change or
> if it is a problem with the user code. To determine that requires
> working with and understanding the user code. It's just impractical for
> me to do that with a large base of code like that.

But you don't have to take the stance that no regressions may occur (for 
this very reason). 

I think automated builds + tests can be useful in different ways:
- the authors of the code can be notified and look at the problem. Some will 
care and help you spot bugs earlier or may fix their own code earlier. This 
is at no cost to you. Eventually, this task can perhaps be delegated 
completely?
- when a lot of stuff breaks, it is an indicator at least.
- while you may need a lot of investment to determine all problems, at least 
some category of problems you may recognize quickly.