Re: Can this be done? Defining type as in this Scala sample code

[drug via Digitalmars-d]

you can do something like this (https://run.dlang.io/is/RYR5Dm):
```
import std.algorithm : sum;
import std.range : only;
import std.stdio : writeln;
import std.typecons : tuple;

void main()
{
    {
        auto list = tuple(1, 2.4, 5);
        auto sum = list.expand.only.sum;
        writeln(sum);
    }

    {
        // do not compile
        /*
        auto list = tuple(1, 2.4, 5, "123");
        auto sum = list.expand.only.sum;
        writeln(sum);
        */
    }
}
```