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Consider the following template
auto foo(T, int W, int H)(T p1, T p2) { }
Is there a "nice" way from the outside the get the names of the template values?
E.g:
pragma(msg, TemplateParameterNames!(foo)); // AliasSeq!("T", "W", "H") or ["T", "W", "H"]
I know you can find the names values in a very hacky way. (atleast in dmd 2.097.1)
template HackyHack(alias T) {
enum RawName = T.stringof;
enum HackyHack = parseRawName(RawName); // Or templateParse!RawString;
}
I currently have the HackyHack solution "working" but I really don't like it and I would be supprised if it works on other dmd version or other compilers.
I know I can do things like:
template foo(T, int W, int H) {
enum names = ... // some magic with __traits or just assing it to ["T", "W", "H"]
auto foo(T p1, T p2) { }
}
Use template mixins or other solutions to get what I want but if possible I prefer to just introspect on the template.
Usecase right now is to do some cuda kernel generation from a D shortfunction.
Something like this:
@kernel
auto saxpy(T, int Iters, int N, int Stride)(T a, T* x, T* y, T* output) => q{
int tid = blockIdx.x * blockDim.x + threadIdx.x;
for(int idx = tid, int i = 0; i < Iters && idx < N; ++i, idx += Stride) {
output[idx] = a * x[idx] + y[idx];
}
};
Would get transformed to:
template<typename T, int Iters, int N, int Stride>
__global__ void saxpy(T a, T* x, T* y, T* output) {
//Identical function body / parameters and template arguments from the @kernel
//D function.
int tid = blockIdx.x * blockDim.x + threadIdx.x;
for(int idx = tid, int i = 0; i < Iters && idx < N; ++i, idx += Stride) {
output[idx] = a * x[idx] + y[idx];
}
}
Really need the names to make this translation, correctly.
Just to be clear i'm not interested in getting the arguments a template was instantiated with. I can use TemplateArgsOf!T for that.
