eiriktsarpalis

let run x = Async.RunSynchronously x

let runParallel (workflow : Async<'T>) =
    [| for i in 1 .. 100 -> workflow |] 
    |> Async.Parallel
    |> run

let a = async { return 42 }
let b = async { return run (async { return 42 })}

eiriktsarpalis

type Cont<'T> = ('T -> unit) -> (exn -> unit) -> unit

let ret t = fun sc _ -> sc t
let (>>=) f g =
    fun sc ec ->
        let sc' (t : 'T) =
            match (try Choice1Of2 (g t) with e -> Choice2Of2 e) with
            | Choice1Of2 g -> g sc ec
            | Choice2Of2 e -> ec e

eiriktsarpalis

type Test =
    static member F<'T>(t : 'T option) = ()
    static member F<'T>(e : 'T -> 'T) = ()

type Foo = { A : int }
type Bar = { A : int }

Test.F(fun (r:Foo) -> { r with A = 32 }) // type checks
Test.F(fun (r:Bar) -> { r with A = 32 }) // type checks
Test.F<Foo>(fun r  -> { r with A = 32 }) // type error

eiriktsarpalis

open System
open System.Reflection

open Microsoft.FSharp.Quotations
open Microsoft.FSharp.Quotations.Patterns
open Microsoft.FSharp.Quotations.DerivedPatterns

type MethodInfo with
    /// Gets the underlying method definition
    /// including the supplied declaring type and method type arguments

eiriktsarpalis

{
  "Success": {
    "_flags": "subtype",
    "subtype": {
      "Case": "GenericTypeInstance",
      "GenericDefinition": {
        "Case": "NamedType",
        "Name": "MBrace.Core.Builders+Bind@331-1",
        "Assembly": {
          "Name": "MBrace.Core",

eiriktsarpalis

open System
open System.Runtime.CompilerServices

type SymbolicException =
    {
        Source : Exception
        Stacktrace : string list
    }

module SymbolicException =

eiriktsarpalis

module Client =
  
    let connectionString = Environment.GetEnvironmentVariable("CONN")
    let session = new Session(connectionString)

    let doA (a : A) = session.Send a
    let doB (b : B) = session.Send b


type Client(connectionString : string) =

eiriktsarpalis

#time "on"

open System
open System.Collections.Generic

let gdata = [|for i in 1 .. 1000000 -> Guid.NewGuid()|]
let sdata = gdata |> Array.map string

// Real: 00:00:17.774, CPU: 00:00:17.703, GC gen0: 378, gen1: 61, gen2: 1
let gmap = ref Map.empty<Guid, int>

eiriktsarpalis

// One of the common annoyances when writing imperative code in F# is that the 
// expression-based nature of the language makes it effectively impossible to 
// break or return in the midst of a for-loop. This is an attempt to encode 
// lightweight cancellation on top of native for loops. As usual, this is intended 
// as a PoC and should not be considered seriously for production code.

module Seq =
    open System.Collections
    open System.Collections.Generic

eiriktsarpalis

Keybase proof

I hereby claim:

• I am eiriktsarpalis on github.
• I am eiriktsarpalis (https://keybase.io/eiriktsarpalis) on keybase.
• I have a public key ASDsjo4ajiE7h4qGM_HbGrq2lco-Kj5LfRn2uCjZ2axtIQo

To claim this, I am signing this object: