Code shared from run.dlang.io. Run with '-unittest'

main.d

void main()
{
    import std.algorithm, std.stdio;

    "Starting program".writeln;

    int[] a = new int[5];

    a = [1, 5, 3, 6, 9];

    for (int i; i < a.length; i++)
        writeln(a[i]);

    a.length = 7;


    for (int i; i < a.length; i++)
        writeln(a[i]);
    // Print the result _during_ compilation
}