Request for comments: std.d.lexer

[Jonathan M Davis]

On Friday, February 08, 2013 23:50:13 Dmitry Olshansky wrote:
> Complication - yes, slight performance cost is what I doubt it in RA
> case. Seems like a compiler/optimizer issue.

The main problem isn't RA ranges. It's quite probable that the optimizer takes 
care of any minor additional overhead that's incurred there. The issue is 
really pure forward ranges, because you're forced to count the code units as 
they're processed (or even save the range as you go along, given how expensive 
it would be to go find the index even if you have it). But we really have no 
way of knowing how bad it is without hard data. It would certainly be trivial 
to end up doing other stuff in the implementation which cost far more.

- Jonathan M Davis