Re: Why does `static foreach` lead to something calling `~=` internally?
On Sunday, 7 July 2019 at 18:45:14 UTC, 0xEAB wrote:
On Sunday, 7 July 2019 at 16:51:57 UTC, 0xEAB wrote:
Why does this `static foreach` lead to hidden usage of operator
Further notes by Dan (aka "Wild"):
I added some small printfs to the compiler, http://ix.io/1NWM
It seems like it lowers it into something weird
Static foreach needs a tuple. When you have a range like "0 ..
10" it has to convert that to a tuple. It does this by generating
some code and running it at CTFE. Guess this was done as it was a
lot simpler to do, you don't have to worry about recreating
ranges as that's already done by using CTFE.
What it ends up lowering to:
https://github.com/dlang/dmd/blob/v2.087.0/src/dmd/cond.d#L274
* static foreach (x; {
* typeof({
* foreach (x; range) return x;
* }())[] __res;
* foreach (x; range) __res ~= x;
* return __res;
* }()) { ... }
Re: Why does `static foreach` lead to something calling `~=` internally?
On Sunday, 7 July 2019 at 16:51:57 UTC, 0xEAB wrote: Why does this `static foreach` lead to hidden usage of operator Further notes by Dan (aka "Wild"): I added some small printfs to the compiler, http://ix.io/1NWM It seems like it lowers it into something weird
Re: Why does `static foreach` lead to something calling `~=` internally?
On Sunday, 7 July 2019 at 17:07:59 UTC, a11e99z wrote: On Sunday, 7 July 2019 at 16:51:57 UTC, 0xEAB wrote: Why does this `static foreach` lead to hidden usage of operator `~=` calls in some cases? probably same oops! this one https://forum.dlang.org/post/eidpgqohllwmuumxw...@forum.dlang.org
Re: Why does `static foreach` lead to something calling `~=` internally?
On Sunday, 7 July 2019 at 16:51:57 UTC, 0xEAB wrote: Why does this `static foreach` lead to hidden usage of operator `~=` calls in some cases? probably same https://forum.dlang.org/post/qd9ee0$2eud$1...@digitalmars.com
Why does `static foreach` lead to something calling `~=` internally?
Why does this `static foreach` lead to hidden usage of operator
`~=` calls in some cases?
static foreach(i; 0 .. cnt)
onlineapp.d(9): Error: cannot use operator ~= in @nogc delegate
onlineapp.xv!(myUDA("/")).__funcliteral2.__lambda1
import std.traits;
private @safe pure nothrow @nogc
{
enum xv(alias uda) = function()
{
enum cnt = 10;
static foreach(i; 0 .. cnt)
{
}
};
}
struct myUDA
{
string path;
}
@myUDA("/")
void doSth(string path)
{
}
extern(C) void main()
{
xv!(getUDAs!(doSth, myUDA))();
}
Try: https://run.dlang.io/is/clQgeA
