DMD 0.170 release

[Walter Bright]

Bill Baxter wrote:
> Hmm.  So that's the main issue then, is it?  To have a reverse iteration 
> on arrays that's as close to a hand-written for-loop as possible?

The major issue is that foreach will usually be used on arrays, and it 
had better produce good code for them, or else people will eshew it and 
stick with for.

> If you could only think of some way to automatically optimize that case 
> to generate the same code...  Is it totally hopeless?

Trying to recognize it out of an opApply is rather difficult.