import std.stdio;

import std.traits;

import std.meta;

​

struct S0

{

    double[3] x;

};

struct S1

{

    double junk0;

    double[3] x;

};

​

union U

{

    S0 s0;

    S1 s1;

}

​

void main()

{

​

    U u;

​

    double* ptr;

​

    u.s0.x = [0.0, 0.1, 0.3];

    u.s1.x = [1.0, 1.1, 1.3];

​

    writeln("typeid( u.tupleof): ", typeid(u.tupleof));

    writeln("typeid( u.tupleof[0]): ", typeid(u.tupleof[0]));

    writeln("typeid( u.tupleof[0].x): ", typeid(u.tupleof[0].x));

​

    writeln();

​

    // indeed both tuples exist

    writeln("u.tupleof[0].x.ptr: ", u.tupleof[0].x.ptr);

    writeln("u.tupleof[1].x.ptr: ", u.tupleof[1].x.ptr);

​

    // this is fine (notice that 'val' is never used

    foreach (i, val; u.tupleof)

    {

        ptr = u.tupleof[i].x.ptr;

        writeln("ptr: ", ptr);

    }

​

    // this is fine too

    static foreach (i; 0 .. u.tupleof.length)

    {

        ptr = u.tupleof[i].x.ptr;

        writeln("ptr: ", ptr);

    }

}