Shortest way to allocate an array and initialize it with a specific value.

[Adel Mamin via Digitalmars-d-learn]

ubyte[5] a = 0xAA; // Fine. Five 0xAA bytes.
auto a2 = new ubyte[5]; // Fine. Five 0 bytes.
Now, let's say, I want to allocate an array of a size, derived at 
run time, and initialize it to some non-zero value at the same 
time. What would be the shortest way of doing it?