Append to 'map' result

[Jean-Louis Leroy via Digitalmars-d-learn]

I want to create a range that consists of the result of a map() 
followed by a value, e.g.:

  int[] x = [ 1, 2, 3];
  auto y = map!(x => x * x)(x);
  auto z = y ~ 99; // how???
I have tried several variations: convert 99 to a dynamic array, 
to a range, convert range to dynamic array (couldn't even figure 
that one); to no avail.

Help please...