On Apr 3, 2009, at 1:50 PM, Daniel Bünzli wrote:
> Le 3 avr. 09 à 18:52, Martin Jambon a écrit :
>> - I see absolutely no practical advantage of having an immutable  
>> "character
>> string" type.
>
> In fact I find the result of the following sequence of operations  
> very disappointing for a functional programming language :
>
>        Objective Caml version 3.11.0
>
> # Sys.os_type;;
> - : string = "Unix"
> # let s = Sys.os_type;;
> val s : string = "Unix"
> # s.[0] <- 'a';;
> - : unit = ()
> # Sys.os_type;;
> - : string = "anix"

Perhaps mutable data of any type should be markable as const, with the  
marking being
permanent.

Or maybe OCaml should have an immutable string wrapper that can be  
created from
a mutable string? Such immutable strings would be returned where the  
string is not supposed
to be further modified.

That's where I like C++/Qt copy-on-write strings a lot. They make life  
easy.

Cheers, Kuba