COW vs. in-place.

[Dawid Ciężarkiewicz]

Dave wrote:

> Dawid Ciężarkiewicz wrote:
>> I'd rather wait till const/immutability in D problem will be resolved.
>> Don't forget that additional "option" is runtime cost. There are some
>> propositions of const/immutability that could help providing compile time
>> information to deal with your proposition.
> 
> It would take many calls to the modified toupper to cost as much as
> needlessly duplicating one large text file, and now you have to either
> live with the dups or write your own in-place toupper <g>

Yes. Still - I'd rather see duplicated functions for that or something like
it (just to have it in compile time).
 
> None of the const/immutability ideas will take care of having to "copy
> on write"; they were all more-or-less just ways of enforcing COW so
> there wouldn't be mistakes.

Well, right.

Maybe just writting new module (std.strinplace) that do what you want and
then sending it to Walter/D discussion group is good . I guess with newday
import improvements names could stay like they were and people interested
in this speedup would statically import this module and use FQN where they
want such behavior.