int[] a = new int[10];
int[10] b;
auto r = chain(a, b[]);
writefln("a %s", typeid(a)); // a int[]
writefln("a[] %s", typeid(a[])); // a[] int[]
writefln("b %s", typeid(b)); // b int[10]
writefln("b[] %s", typeid(b[])); // b[] int[]
writefln("r %s", typeid(r)); // r std.range.chain!(int[], int[]).chain.Result
// writefln("r[] %s", typeid(r[])); ERROR
pragma(msg, typeof(points));