An example or generators in Vala

class Test
{
	static void generate(Generator gen)
	{
		int[] values = new int [] {100, 200, 300, 400, 500, 0};
		int i;

		for(i=0; values[i] != 0; i++)
		{
			gen.yield(values[i]);
			Thread.usleep(500000);
		}
	}

	static void main(string[] args)
	{
		Generator gen = new Generator(generate);
		gen.start();
		int value;
		while(gen.next(ref value))
		{
			stdout.printf("Value = %d\n", value);
		}
	}
}