Why I love F#: Option Types

Dustin Campbell goes over F# option types. Option types are a simple example of a discriminated (or tagged) union, although understanding that isn't necessary in order to use them. Simply put, an option type wraps a value with information indicating whether or not the value exists. For C# or VB programmers, it may be convenient to think of option types as a mutant cross between .NET 2.0 nullable types and the null object design pattern.