On 05/21/2010 11:55 AM, Ellery Newcomer wrote:
On 05/21/2010 09:14 AM, Steven Schveighoffer wrote:
Second, since reference types are the right thing to do, classes are
much easier to deal with. I know AA's are reference types that are
structs, but the code needed to perform this feat is not trivial. The
AA has only one member, a reference to the data struct, which is
allocated on the heap. Any member function/property that is used on
the AA must first check whether the implementation is allocated yet.
The only benefit this gives you IMO is not having to use 'new' on it.
And even that has some drawbacks. For example, pass an empty AA by
value to a function, and if that function adds any data to it, it is
lost. But pass an AA by value with one element in it, and the new data
sticks. A class gives you much more in terms of options -- interfaces,
builtin synchronization, runtime comparison, etc. And it forces full
reference semantics by default. I think regardless of whether
interfaces are defined for dcollections, classes give a better set of
options than structs.
Wow. A partially-nullable type.
Great. Now I have to review everywhere I ever used an AA. Thanks, D.
is there any serious drawback to something like
(int[int]).init = InitializedAA!(int,int)
?
Or should one just always give an AA param either a const or ref modifier?
