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Option.map<'T,'U> Function (F#)

  • Artykuł

Transforms an option value by using a specified mapping function.

Namespace/Module Path: Microsoft.FSharp.Core.Option

Assembly: FSharp.Core (in FSharp.Core.dll)

// Signature:
map : ('T -> 'U) -> 'T option -> 'U option

// Usage:
map mapping option

Parameters

  • mapping
    Type: 'T -> 'U

    A function to apply to the option value.

  • option
    Type: 'T option

    The input option.

Return Value

An option of the result of applying the mapping function, or None if the input is None.

Remarks

The expression map f inp evaluates to match inp with None -> None | Some x -> Some (f x).

This function is named Map in compiled assemblies. If you are accessing the function from a language other than F#, or through reflection, use this name.

Platforms

Windows 7, Windows Vista SP2, Windows XP SP3, Windows XP x64 SP2, Windows Server 2008 R2, Windows Server 2008 SP2, Windows Server 2003 SP2

Version Information

F# Runtime

Supported in: 2.0, 4.0

Silverlight

Supported in: 3

See Also

Reference

Core.Option Module (F#)

Microsoft.FSharp.Core Namespace (F#)