Is there any built-in, or library-provided way to map a set of variadic template arguments in D?
For example:
void foo(Args...)(Args args)
{
bar(fun(args));
}
I want that to expand to:
void foo(Args...)(Args args)
{
bar(fun(args[0]), fun(args[1]), fun(args[2]), /* ... */);
}
C++11 variadic templates support this. How do you do the same in D?
This is the best I've come up with:
auto staticMappedCall(alias call, alias F, T...)(T t)
{
T a;
foreach(i, arg; t)
a[i] = F(arg);
return call(a);
}
You use it like this:
staticMappedCall!(bar,t)(1, 2);
Where bar is the function to call and t is the transformation.
void bar(int a, int b) { writeln(a, " ", b); }
int t(int a) { return a*2; }
staticMappedCall!(bar, t)(1, 2);
> test
2 4