Re: protocol for using InputRanges

[w0rp]

I should add that I have implemented some ranges where .front and 
.popFront are both nothrow, as !empty doesn't "advance and cache" 
for these ranges and the check is moved into an in{} contract. 
For these ranges, they tend to behave like arrays with bounds 
checking, only now the bounds checking is turned off by virtue of 
-release.