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Patterns.Value Active Pattern (F#)

  • Article

Recognizes expressions that represent a constant value.

Namespace/Module Path: Microsoft.FSharp.Quotations.Patterns

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

// Signature:
( |Value|_| ) : (input:Expr) -> (obj * Type) option

Parameters

  • input
    Type: Expr

    The input expression to match against.

Return Value

The formal return type is (obj * Type) option. The option return type indicates whether the input results in a match. In a pattern matching expression, the input is decomposed, upon a successful match, into a tuple of two elements.

The first element of the tuple is an object that represents a literal value. The second element is the type of the object, represented by a Type object.

Remarks

This function is named ValuePattern in the .NET Framework assembly. If you are accessing the member from a .NET Framework language other than F#, or through reflection, use this name.

Platforms

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

Version Information

F# Core Library Versions

Supported in: 2.0, 4.0, Portable

See Also

Reference

Quotations.Patterns Module (F#)

Microsoft.FSharp.Quotations Namespace (F#)