Testing for Nil

[Mike_Cotrone]

Convenient

How to check for leap year

Well, depending on the application you can have historical dates before 1901, and future dates of 2100+. So very much depends on the application. I plan on retiring before worrying about years beyond 9999, so will let @Kem Tekinay resolve those. As somebody once said, “I plan on being immortal. So far, so good.”