The demise of T[new]

[Ary Borenszweig]

Walter Bright wrote:
> The purpose of T[new] was to solve the problems T[] had with passing T[] 
> to a function and then the function resizes the T[]. What happens with 
> the original?
> 
> The solution we came up with was to create a third array type, T[new], 
> which was a reference type.
> 
> Andrei had the idea that T[new] could be dispensed with by making a 
> "builder" library type to handle creating arrays by doing things like 
> appending, and then delivering a finished T[] type. This is similar to 
> what std.outbuffer and std.array.Appender do, they just need a bit of 
> refining.
> 
> The .length property of T[] would then become an rvalue only, not an 
> lvalue, and ~= would no longer be allowed for T[].
> 
> We both feel that this would simplify D, make it more flexible, and 
> remove some awkward corner cases like the inability to say a.length++.
> 
> What do you think?

I remember seeing a lot of CTFE code that created a dynamic array and 
then appended stuff to it, like for example to build a list of prime 
numbers. Would that still work with ArrayBuilder?