Deque impl.

[Robert burner Schadek]

On 01/31/2013 08:33 AM, d coder wrote:
>> To be honest deque can be implemented far better if random access as in
>> indexing, removal and such is dropped.
> As other people too pointed out, Deque is indeed a random access
> range, so indexing operator is a must. Insert/Remove too are good to
> have. Array implementation in the std.container too implements remove
> and insert.
>
> Another small issue is that this Deque implementation is a Class.
> std.container provides all the containers as structs. So for sake of
> consistency, we should implement Deque too as a struct.
Thats not totally correct. The Rb tree is a class. But the real reason 
for the Deque being a class
is that it holds two value members. And if you pass the Deque around you 
need to do this as ref.
Otherwise you shall not call any method that modifies this value 
members, because this will only be
visible at the calling site. See this tiny example:

struct F {
     size_t a;
}

void foo(F f) {
     f.a = 10;
}

void main() {
     F a;
     a.a = 9;
     foo(a);
     assert(a.a == 10);
}

So I think leaving it a class is valid. But I could create a static 
opCall method that creates a Deque or a
convince Function similar to that of the Rb tree

>
> Regards
> - Puneet