CI Provider | Status |
---|---|
Travis CI | |
AppVeyor |
The Unit type allows only one value which is empty. This is similar to the System.Void
type (void
keyword) which can sadly not be used by user code. Using the Unit type as return value instead of void
offers some benefits, such as the deprecation of non-generic or special classes for the purpose of communicating the absence of a return value (Task<Unit>
would replace Task
, Func<Unit>
et al. would make Action
et al. obsolete).
Other languages, such as F#, Haskell or Scala already provide a Unit type, but Microsoft chose to prevent using the existing System.Void
type in C# user code in favor of the void
keyword.
Use Unit
as return value instead of the void
keyword.
// use
using TheVoid;
public Unit DoSomething() {
//...
}
// instead of
public void DoSomething() {
//...
}
To "return" Unit simply use one of the following
Unit.Default
(recommended)default(Unit)
new Unit()
- @gregoryyoung created a similar type which he called
Nothing
but it missed some things. - @Reactive-Extensions the .net project contains a
System.Unit
type which is not available as a standalone package.
This project is deprecated as soon as any Unit type is included in C#.