Jenkins Hash Function

One of Jenkin's hash functions

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module Hash
 
let jenkins (s:string) =
    let h = 
        System.Text.Encoding.ASCII.GetBytes(s) |> Array.fold (fun ac b ->
            let ac = ac + (uint32 b)
            let ac = ac + (ac <<< 10)
            ac ^^^ (ac >>> 6)
        ) 0u
    let h = h + (h <<< 3)
    let h = h ^^^ (h <<< 11)
    h + (h <<< 15)

module Hash

val jenkins : s:string -> uint32

Full name: Hash.jenkins

val s : string

Multiple items
val string : value:'T -> string

Full name: Microsoft.FSharp.Core.Operators.string

--------------------
type string = System.String

Full name: Microsoft.FSharp.Core.string

val h : uint32

namespace System

namespace System.Text

type Encoding =
  member BodyName : string
  member Clone : unit -> obj
  member CodePage : int
  member DecoderFallback : DecoderFallback with get, set
  member EncoderFallback : EncoderFallback with get, set
  member EncodingName : string
  member Equals : value:obj -> bool
  member GetByteCount : chars:char[] -> int + 3 overloads
  member GetBytes : chars:char[] -> byte[] + 5 overloads
  member GetCharCount : bytes:byte[] -> int + 2 overloads
  ...

Full name: System.Text.Encoding

property System.Text.Encoding.ASCII: System.Text.Encoding

System.Text.Encoding.GetBytes(s: string) : byte []
System.Text.Encoding.GetBytes(chars: char []) : byte []
System.Text.Encoding.GetBytes(chars: char [], index: int, count: int) : byte []
System.Text.Encoding.GetBytes(chars: nativeptr<char>, charCount: int, bytes: nativeptr<byte>, byteCount: int) : int
System.Text.Encoding.GetBytes(s: string, charIndex: int, charCount: int, bytes: byte [], byteIndex: int) : int
System.Text.Encoding.GetBytes(chars: char [], charIndex: int, charCount: int, bytes: byte [], byteIndex: int) : int

module Array

from Microsoft.FSharp.Collections

val fold : folder:('State -> 'T -> 'State) -> state:'State -> array:'T [] -> 'State

Full name: Microsoft.FSharp.Collections.Array.fold

val ac : uint32

val b : byte

Multiple items
val uint32 : value:'T -> uint32 (requires member op_Explicit)

Full name: Microsoft.FSharp.Core.Operators.uint32

--------------------
type uint32 = System.UInt32

Full name: Microsoft.FSharp.Core.uint32

Raw view Test code New version

More information

Link:	http://fssnip.net/mY
Posted:	10 years ago
Author:	RViscarra
Tags:	hash , jenkins