Spans.fs

[<MemoryDiagnoser>]
type Betch() =
    let s = "123 456"

    [<Benchmark(Baseline = true)>]
    member __.Array() =
        let [|foo; bar|] = s.Split ' '
        let _x = 
            match BigInteger.TryParse foo, Int32.TryParse bar with
            | (true, x), (true, y) -> x, y
            | _ -> failwith "oops"
        ()

    [<Benchmark>]
    member __.Span() =
        let idx = s.IndexOf ' '
        let foo = s.AsSpan(0, idx)
        let bar = s.AsSpan(idx + 1)
        let _x = 
            match BigInteger.TryParse foo, Int32.TryParse bar with
            | (true, x), (true, y) -> x, y
            | _ -> failwith "oops"
        ()

[<EntryPoint>]
let main _ =
    BenchmarkRunner.Run<Betch>() |> ignore
    0  




BenchmarkDotNet=v0.10.14, OS=Windows 10.0.17134
Intel Core i5-7600 CPU 3.50GHz (Kaby Lake), 1 CPU, 4 logical and 4 physical cores
.NET Core SDK=2.1.301
  [Host]     : .NET Core 2.1.1 (CoreCLR 4.6.26606.02, CoreFX 4.6.26606.05), 64bit RyuJIT DEBUG
  DefaultJob : .NET Core 2.1.1 (CoreCLR 4.6.26606.02, CoreFX 4.6.26606.05), 64bit RyuJIT


 Method |     Mean |    Error |   StdDev | Scaled |  Gen 0 | Allocated |
------- |---------:|---------:|---------:|-------:|-------:|----------:|
  Array | 418.1 ns | 3.346 ns | 3.130 ns |   1.00 | 0.0787 |     248 B |
   Span | 346.7 ns | 4.160 ns | 3.891 ns |   0.83 | 0.0453 |     144 B |
   
   
   
   
BenchmarkDotNet=v0.10.14, OS=macOS High Sierra 10.13.5 (17F77) [Darwin 17.6.0]
Intel Core i5-7600 CPU 3.50GHz (Kaby Lake), 1 CPU, 4 logical and 4 physical cores
.NET Core SDK=2.1.301
  [Host]     : .NET Core 2.1.1 (CoreCLR 4.6.26606.02, CoreFX 4.6.26606.05), 64bit RyuJIT DEBUG
  DefaultJob : .NET Core 2.1.1 (CoreCLR 4.6.26606.02, CoreFX 4.6.26606.05), 64bit RyuJIT


 Method |     Mean |     Error |    StdDev | Scaled | ScaledSD |  Gen 0 | Allocated |
------- |---------:|----------:|----------:|-------:|---------:|-------:|----------:|
  Array | 511.0 ns |  9.020 ns |  8.437 ns |   1.00 |     0.00 | 0.0782 |     248 B |
   Span | 426.5 ns | 11.596 ns | 14.240 ns |   0.83 |     0.03 | 0.0453 |     144 B |