Critque of Rust's collection types

[cym13 via Digitalmars-d]

On Wednesday, 14 September 2016 at 11:59:13 UTC, Kagamin wrote:
> On Wednesday, 14 September 2016 at 00:36:39 UTC, Walter Bright 
> wrote:
>> Of particular interest is the advocacy of collision attack 
>> resistance. Is anyone interested in exploring this w.r.t. D's 
>> builtin hashes?
>
> Perl's approach is probably good enough 
> https://issues.dlang.org/show_bug.cgi?id=14414
> Reversibility of the hash looks irrelevant for dos attack.

What do you mean by that? It's the basis of DoS attack against 
hashtables: being able to find many inputs with the same hash. 
What perl does isn't good IMHO because their solution is not the 
default behaviour and the security effect of changing the seed 
isn't made obvious to the programmer.

While I can understand prefering speed over security as default 
(although history shows that if it's not the default it's not 
used) I would rather have a security flag to change the algorithm 
at compile-time for a more secure one. Most programmers won't see 
the point of changing seed and we can definitely take advantage 
of templates here.

Also I'm not sure in our use-case fastest necessarily means less 
secure, there should be some benchmarking at work.