[Home] Type Microsoft.FSharp.Core.Option


The type of optional values. When used from other .NET languages the empty option is the null value. Use the constructors Some and None to create values of this type. Use the values in the Option module to manipulate values of this type, or pattern match against the values directly. None values will appear as the value null to other .NET languages. Instance methods on this type will appear as static methods to other .NET languages due to the use of null as a value representation.

Full Type Signature

[<DefaultAugmentationAttribute (false);
  CompilationRepresentationAttribute (enum<CompilationRepresentationFlags> (8))>]
type Option<'a> =
  | None
  | Some of 'a
  with
    static member Some : 'a -> 'a option
    member IsNone : bool
    member IsSome : bool
    static member None : 'a option
    [<CompilationRepresentationAttribute (enum<CompilationRepresentationFlags> (2))>]
    member Value : 'a
  end

Instance Members

MemberDescription
member IsNone : bool
 Return 'true' if the option is a 'None' value. 
member IsSome : bool
 Return 'true' if the option is a 'Some' value. 
[<CompilationRepresentationAttribute
  (enum<CompilationRepresentationFlags> (2))>]
member Value : 'a
 Get the value of a 'Some' option. A NullReferenceException is raised if the option is 'None'.

Static Members

MemberDescription
member None : 'a option
 Create an option value that is a 'None' value. 
member Some : 'a -> 'a option
 Create an option value that is a 'Some' value.

See Also

Microsoft.FSharp.Core


Documentation for assembly FSharp.Core, version 1.9.6.0, generated using F# Programming Language version 1.9.6.0