On Tue, Aug 25, 2020 at 03:41:06AM +0000, Jon Degenhardt via
Digitalmars-d-learn wrote:
> What's the best way to get the element type of an array at compile
> time?
>
> Something like std.range.ElementType except that works on any array
> type. There is std.traits.ForeachType, but it wasn't clear if that
> was the right thing.
[...]
alias T = ... /* the type to inspect */
static if (is(T : E[], E)) {
... /* in this block, E is the element type */
}
Or if you need to use it in another expression:
template ArrayElemType(T) {
static if (is(T : E[], E)) {
alias ArrayElemType = E;
}
else
alias ArrayElemType = void;
// or static assert(0) if it should be an error
}
int[] myArr;
pragma(msg, ArrayElemType!(typeof(myArr))); // int
string myStr;
pragma(msg, ArrayElemType!(typeof(myStr))); // immutable(char)
T
--
The best way to destroy a cause is to defend it poorly.
