A 5 minute lightning talk given at SHDH 40 on F#.

1. Some F# Highlights Matt Harrington mbh.work@gmail.com

2. Dealing With Concurrency Hire an expert, or … Software Transactional Memory, or … Functional Programming. -Unknown

3. Free, as in beer Free standalone compiler for .NET (Windows or Mono). Syntax highlighting for TextMate, vim, emacs, TextPad, jedit, and others. IDEs: MonoDevelop SharpDevelop Visual Studio Shell Microsoft Research Shared Source License

4. Robin Milner University of Edinburgh ML – 1970s Don Syme MSR Cambridge F# - 2002 Xavier Leroy, et al. INRIA, France Ocaml - 1996

7. Asynchronous programming

8. Pipeline operator |>

9. Currying

10. Continuations

11. MemoizationFirst class functions Immutability Recursion Type inference Pattern matching Lists, sequences, tuples, records, discriminated unions Optiontype

12. OO Classes Inheritance Interfaces Structs Properties Delegates Enums Mutability

13. Tail Call Optimization .method public static int32 g(int32 x) cil managed { .maxstack 5 L_0000: nop L_0001: ldarg.0 L_0002: ldc.i4.0 L_0003: ble.s L_0007 L_0005: br.s L_0009 L_0007: br.s L_0019 L_0009: newobj instance void Program/g@9::.ctor() L_000e: ldarg.0 L_000f: ldc.i4.1 L_0010: sub L_0011: tail L_0013: call int32 Program::f(class [FSharp.Core]Microsoft.<snip>) L_0018: ret L_0019: ldarg.0 L_001a: ret }

14. Units of Measure [<Measure>] type kilogram letbowlingBall = 7.26<kilogram> let force (mass: float<kilogram>) = mass * 9.8

15. Pipeline operator let numbers = [1 .. 100] let square x = x * x letsumOfSquares = numbers |> List.mapsquare |> List.sum

16. Euler Problem #7 let isPrimenum = letupperDivisor = int32(sqrt(float num)) matchnumwith | 0 | 1 -> false | 2 -> true | n ->seq { 2 .. upperDivisor } |> Seq.forall(fun x ->num % x <> 0) let primes = Seq.initInfinite id |> Seq.filterisPrime let nthPrime n = Seq.nth n primes printfn "The 10001st prime number is %i." (nthPrime 10001) Code from "Juliet" on StackOverflow.

17. More… Matt Harrington: mbh.work@gmail.com SFsharp.org Luca Bolognese’s video (see links on SFsharp.org) Programming F# by Chris Smith