On Wed, 26 Jan 2011 18:33:45 -0500, spir <denis.s...@gmail.com> wrote:
On 01/26/2011 07:23 PM, Steven Schveighoffer wrote:
On Wed, 26 Jan 2011 12:27:37 -0500, spir <denis.s...@gmail.com> wrote:
Hello,
This fails:
class T0 {}
class T1 : T0 {}
class T2 : T0 {}
unittest {
auto t1 = new T1();
auto t2 = new T2();
T0[] ts = [t1, t2];
}
Error: cannot implicitly convert expression (t1) of type __trials__.T0
to
__trials__.T2
Error: cannot implicitly convert expression ([(__error),t2]) of type
T2[] to
T0[]
I guess it should be accepted due to explicite typing 'T0[]'. What do
you
think? D first determines the type of the last element (always the
last one),
here T2. Then, /ignoring/ the array's defined type, tries to cast other
elements to the same type T2. It should instead, I guess, check all
elements
are compatible with the defined array type.
An additional enigma is why the failing element t1 is said to be of
supertype
T0 --which is also correct-- while it retained t2's exact type T2. ???
Anyway, is there a workaround?
auto ts = cast(T0[])[t1, t2];
Nope, refused for the same reason (tried to construct [t1,t2] before
casting it).
Hm.. maybe that only works on array literals with all literal elements. I
expected the cast to affect the type the compiler is expecting.
For example, this works:
cast(ubyte[])[1,2]; // without cast typed as int[]
I believe there should be a way to tell the array literal "this is the
type you should be." If that's not possible, then it needs to be added.
If it's expected the cast should work, then I'd file a bug against it.
-Steve
