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Seq.exactlyOne<'T> Function (F#)

  • Article

Returns the only element of the sequence.

Namespace/Module Path: Microsoft.FSharp.Collections.Seq

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

// Signature:
exactlyOne : seq<'T> -> 'T
// Usage:
Seq.exactlyOne source

Parameters

  • source
    Type: seq<'T>

    The input sequence.

Exceptions

Exception

Condition

ArgumentException

Thrown when the input does not have precisely one element.

ArgumentNullException

Thrown when the input sequence is null.

Return Value

The last element of the sequence.

Remarks

This function is named ExactlyOne in the .NET assembly. If accessing the member from a .NET 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

.0

See Also

Reference

Collections.Seq Module (F#)

Microsoft.FSharp.Collections Namespace (F#)