public void TryGetFirst2 ()
{
#region TryGetFirst2
var seq = new int[]{0, 1, 2};
int first;
Assert.IsTrue (seq.TryGetFirst (v => v.IsOdd (), out first));
Assert.IsTrue (1 == first);
Assert.IsTrue (seq.TryGetFirst (v => v.IsEven (), out first));
Assert.IsTrue (0 == first);
Assert.IsFalse (seq.TryGetFirst (v => v == 5, out first));
Assert.IsTrue (0 == first);
#endregion
}