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Patterns.Value Active Pattern (F#)

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 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

Quotations.Patterns Module (F#)

Microsoft.FSharp.Quotations Namespace (F#)