On 03/10/2010 06:47 PM, grauzone wrote:
Andrei Alexandrescu wrote:
On 03/10/2010 06:06 PM, grauzone wrote:
Andrei Alexandrescu wrote:
On 03/10/2010 05:01 PM, grauzone wrote:
Andrei Alexandrescu wrote:
There's one final nail in the coffin. In wake of concurrency, de jure
immutability becomes a necessity, not a useful and desirable de facto
convention. Adopting the window dressing but not the essence of FP by
a concurrent language evokes to me a scene in the Marx Brothers: an
otherwise impeccably-dressed gentleman who forgot to put his pants
on.
Language support is not strictly necessary to get the same effects as
immutable types, as far as multithreading is concerned: small data can
be copied, and large data can be made read-only by OS syscalls. This
just had to be in the message passing library. (As a bonus, it isn't
possible to subvert these mechanisms just by casting.)
That'll never work. The OS granularity is 4KB increments.
Data this small you would simply copy. Because it's so small, copying
won't have negative performance impact. The OS approach can be used for
large data (at least in the order of hundreds of KB) and immutable parts
of the data segment.
Trust me, that will never work anywhere close to satisfactory. It's
even useless to talk about it.
Just saying "it won't work" is a bit empty. Do you happen to have any
arguments?
I'd need to build a fair amount of background, which I don't have time for.
Andrei
