On Tuesday, 28 August 2018 at 13:05:15 UTC, bauss wrote:
On Tuesday, 28 August 2018 at 12:28:19 UTC, Andrey wrote:
Hello,
Let we have two variadic templates:
template Qwerty(Values...) {}
template Qaz(alias type, Data...) {}
Now I want to add a constraint to "Qwerty" so that each type
in "Values" pack must be a "Qaz" template. I don't care about
values of "type" or "Data" in "Qaz".
How to do it in D?
I'm not sure if there is a better way, but isInstanceOf
(std.traits) seems to work with a static foreach and a static
if.
template Qwerty(Values...)
{
static foreach (value; Values)
{
static if (!isInstanceOf!(Qaz, value))
{
static assert(0, "Values are not Qaz only ...");
}
}
// ...
}
https://dlang.org/phobos/std_traits.html#TemplateOf
maybe...
