Hi there Muhammad,

What you're looking for is already possible in the reflection capabilities added in C++26 - you can return a std::meta::info which represents the reflection of a type and splice it to use that type.

To rewrite one of your examples:

consteval auto select_type(int n) {
    return n == 0 ? ^^int : ^^double;
}

Which can then be accessed in non-reflection code via

using T = [: select_type(1) :];

And this is just the tip of the iceberg in terms of what is possible with reflection and rewriting template patterns into something which more resembles typical C++ code.

Does this about cover what you were wanting to make possible, or is there some extra layer to it which I've missed?