On Sunday, 28 September 2014 at 19:06:09 UTC, Marc Schütz wrote:
On Sunday, 28 September 2014 at 16:12:53 UTC, Meta wrote:
On Sunday, 28 September 2014 at 08:01:00 UTC, Nordlöw wrote:
Is there a reason why isArray!T doesn't match T when T is a
std.container.Array? I'm asking because after looking into
msgpack-d because of
http://forum.dlang.org/thread/aclapseyptgcwntda...@forum.dlang.org#post-aclapseyptgcwntdavwt:40forum.dlang.org
I realized that this is the reason why msgpack doesn't
correctly pack std.container.Array.
It's just an oversight in isArray as far as I can tell. I
don't know if there's any specific reason that Array is not
considered an array.
I don't think so. std.container.Array is just a data structure
that behaves like an array, but there could be countless other
user defined data structures. It should not get preferred
treatment over those other types. At most, isArray could check
for the presence of .length, .ptr and indexing/slicing. But I
think isArray was intended specifically for built-in arrays.
It's description "is an array (static or dynamic [...])" is
probably meant to express that, because it lists static and
dynamic arrays, but doesn't mention array-like containers.
Yes, everything here is correct.
Interestingly though, "Array" is not actually "array-like" (it's
not a range, it doesn't slice), however "Array.Range" *is* an
array-like structure.
In regards to "isArrayLike", it would probably be more
interesting to instead integrate it as a "isRandomAccessRange"
range refinement, which would also allow "opSlice" operations, eg
(myRange[0 .. 3] = 5).
As for ".ptr", I think no range *trait* should expose (require)
that, as it would most probably be an underhanded way to leak
some abstraction, which would be better expressed as a direct
call *prior*, rather than a range proper. EG:
myRange.ptr[0 .. 10].doSomeOperation();
