var target = Argument("target", "B");

var dataList = new List<string>();

Task("A")
    .Does(() =>
{
    Information(string.Format("A - List has {0} entries", dataList.Count));
    dataList.AddRange(new string[] {"rod", "jane", "freddy"});
    Information(string.Format("A - List has {0} entries", dataList.Count));
});

Task("B")
    .IsDependentOn("A")
    .DoesForEach(dataList, (s) => Information(string.Format(">>> {0}", s)));

RunTarget(target);