On Tuesday, 2 May 2017 at 09:50:50 UTC, ANtlord wrote:
On Tuesday, 2 May 2017 at 08:24:09 UTC, evilrat wrote:
Making enum means that value should be available at compile
time and AA's are fully dynamic. But if my memory serves me
well, you can declare empty AA and delay initialization. So
the closest solution is to move initialization of AA to shared
module ctor(note that there is difference between shared and
non-shared, refer to documentation) such as in this example:
--------------------------------
static shared this() // <-- module ctors run before main()
{
dict = [
"s": "q",
"ss": "qq"
];
}
string[string] dict;
void main()
{ ... dict is already initialized ... }
I know about D's enums and I know about module ctors but my
question is about difference between array and associative
array in case of definition in top level of module. Why DMD
allows to define array and doesn't allow to define associative
array.
Because it is perfectly fine. They are live in the module scope,
which has its own life time, and from runtime or lifetime
perspective there is no difference here. And since array can be
fixed-sized it is valid to use as enum value. But there is one
catch, in case of enum array it is best to avoid it in favor of
immutable array* because every time you reference it it will
allocate. But thats the difference between enum and not enum, not
the array and map.
This is what I remember from the past, and it is possibly that no
longer relevant anymore.
* not sure if it prevents allocation though, but in theory it
should since it *should* go in to program data section when
compiling
