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Patterns.Call Active Pattern (F#)

Den Delimarsky|Last Updated: 8/18/2017
1 Contributor

Recognizes expressions that represent calls to static and instance methods, and those that represent and functions defined in modules.

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

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


// Signature:
( |Call|_| ) : (input:Expr) -> (Expr option * MethodInfo * Expr list) option


input Type: Expr

The input expression to match against.

Return Value

The formal return type is (Expr option * MethodInfo * Expr list) option. The option 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 three elements. The first element is an option for an expression that represents the reference to the object for an instance method call. It has a value only if the call is an instance method. The second element of the tuple is a T:System.Reflection.MethodInfo object that describes the method. The final element of the tuple is a list that contains the arguments for the method call.


This function is named CallPattern 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.


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

Quotations.Patterns Module (F#)

Microsoft.FSharp.Quotations Namespace (F#)

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