Seq.distinct<'T> Function (F#)
Returns a sequence that contains no duplicate entries according to generic hash and equality comparisons on the entries. If an element occurs multiple times in the sequence then the later occurrences are discarded.
Namespace/Module Path: Microsoft.FSharp.Collections.Seq
Assembly: FSharp.Core (in FSharp.Core.dll)
// Signature:
Seq.distinct : seq<'T> -> seq<'T> (requires equality)
// Usage:
Seq.distinct source
Parameters
source
Type: seq<'T>The input sequence.
Exceptions
Exception |
Condition |
|---|---|
Thrown when the input sequence is null. |
Return Value
The result sequence.
Remarks
This function is named Distinct in compiled assemblies. If you are accessing the function from a language other than F#, or through reflection, use this name.
Example
The following example demonstrates the use of Seq.distinct. The example generates the binary representation of a number as a sequence. It then determines that the only unique numbers are 0 and 1.
let binary n =
let rec generateBinary n =
if (n / 2 = 0) then [n]
else (n % 2) :: generateBinary (n / 2)
generateBinary n |> List.rev |> Seq.ofList
printfn "%A" (binary 1024)
let resultSequence = Seq.distinct (binary 1024)
printfn "%A" resultSequence
[1; 0; 0; 0; 0; 0; 0; 0; 0; 0; 0] seq [1; 0]
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