gistfile1.txt

module Benchmarks.FSharp.FormatBenchmark

open System
open System.Text
open BenchmarkDotNet.Attributes
open BenchmarkDotNet.Jobs

let ignoreFormatting = String.Equals("abc", "ABC", StringComparison.OrdinalIgnoreCase)

let inline ignoreAndReturnDefault _ = Unchecked.defaultof<'b>

type T = T with
    static member inline ($) (T, arg: unit) = ()
    static member inline ($) (T, arg: int) = 0 // mandatory second terminal case; is unused in runtime but is required for the code to compile
    static member inline ($) (T, func: ^a -> ^b) : ^a -> ^b = fun (_ : 'a) -> T $ Unchecked.defaultof<'b>

let inline negate() : 'a = T $ Unchecked.defaultof<'a>

let inline debugLog format : 'a =
    if ignoreFormatting then
       T $ Unchecked.defaultof<'a>
    else
        Printf.kprintf (printfn "%A: %s" DateTime.Now) format

[<MemoryDiagnoser>]
[<SimpleJob(RuntimeMoniker.NetCoreApp31)>]
[<SimpleJob(RuntimeMoniker.NetCoreApp50)>]
type Formatter() =
    let someNum = DateTime.Now.Millisecond;
    let someString = DateTime.Now.ToString()
    let someDate = DateTime.Now

    let sb = StringBuilder(128)

    [<Benchmark>]
    member _.FormatSprintf() = sprintf "%i %s %O" someNum someString someDate

    [<Benchmark>]
    member _.FormatStringFormat() = String.Format("{0} {1} {2}", someNum, someString, someDate)

    [<Benchmark>]
    member _.FormatSB() = Printf.bprintf sb "%i %s %O" someNum someString someDate
                          let result = sb.ToString()
                          sb.Clear() |> ignore
                          result

    [<Benchmark>]
    member _.FormatInterpolation() = $"{someNum} {someString} {someDate}"

    [<Benchmark>]
    member _.DebugLogCustomFormat() = debugLog "%i %s %O %A" someNum someString someDate (Exception "")

    [<Benchmark>]
    member _.DebugLogStringFormat() = debugLog "sdassda"