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QueryBuilder.HeadOrDefault<'T,'Q> Method (F#)

A query operator that selects the first element of those selected so far, or a default value if the sequence contains no elements.

Namespace/Module Path: Microsoft.FSharp.Linq

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

// Signature:
member this.HeadOrDefault : QuerySource<'T,'Q> -> 'T

// Usage:
queryBuilder.HeadOrDefault (source)

Parameters

Return Value

The first element, or the default value for the type.

Remarks

For more information and examples, see Query Expressions (F#).

Platforms

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

Version Information

F# Core Library Versions

Supported in: 4.0, Portable

See Also

Reference

Linq.QueryBuilder Class (F#)

Microsoft.FSharp.Linq Namespace (F#)

Query Expressions (F#)