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Expand the table of content<'T,'U> Function (F#)

Den Delimarsky|Last Updated: 8/18/2017
2 Contributors

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


mapping Type: 'T -> 'U

A function to apply to the option value.

option Type: 'Toption

The input option.

Return Value

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


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.


Windows 8, Windows 7, Windows Server 2012, Windows Server 2008 R2

Version Information

F# Core Library Versions

Supported in: 2.0, 4.0, Portable, Portable

See Also

Core.Option Module (F#)

Microsoft.FSharp.Core Namespace (F#)

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