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Static Methods on Interfaces

Use Cases

1. Define related sets or sequences of algorithms to be defined together (need explicit example)
2. Specify required static extension methods for implementing things like LINQ or Rx.
3. Transducers cannot currently be implemented efficiently in .NET. Transducers would need to use IEnumerable<_> as a base collection type rather than potentially more efficient implementations (or retaining the input's stype, e.g. List<_>, etc).
4. F# modules such as List, Array, and Seq all provide functions that are the same in nature but differ by wrapper type.

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type Op =
    | Add
    | Multiply
    static member TryParse input =
        match input with
        | "add" -> Some Add
        | "multiply" -> Some Multiply
        | _ -> None

type Command<'a> =

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open System

type FSharp.Control.AsyncBuilder with
    [<CustomOperation("and!", IsLikeZip=true)>]
    member __.Merge(x, y, f) =
        async {
            let! token = Async.CancellationToken
            let! x' = Async.StartChildAsTask x
            let! y' = Async.StartChildAsTask y
            do System.Threading.Tasks.Task.WaitAll([|x';y'|], cancellationToken = token)

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#load "load-references-debug.fsx"
open System.Data.SqlClient
open FSharp.Data

[<Literal>]
let MasterCS = "Server=.;Database=master;Integrated Security=true;"

let createDB () =
    use cmd = new SqlCommandProvider<"create database Test", MasterCS>(MasterCS)
    cmd.Execute() |> ignore

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// type for fizzbuzz results
type FizzBuzzResult =
    | FizzBuzz
    | Fizz
    | Buzz
    | Number of int

let fizzbuzz n =
    match n % 3, n % 5 with
    | 0, 0 -> FizzBuzz

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using System;
using System.Linq.Expressions;

namespace Foundation.Specifications
{
    /// <summary>
    /// Defines an abstract class from which to create conditional specifications.
    /// </summary>
    /// <typeparam name="T">The type of entity used in the specification.</typeparam>
    /// <seealso href="http://ubik.com.au/article/named/implementing_the_specification_pattern_with_linq" />

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> defineGenericDelegate [| typeof<Collections.Generic.IDictionary<string, obj>>; typeof<Threading.Tasks.Task> |];;
val it : Type =
  System.Func`2[System.Collections.Generic.IDictionary`2[System.String,System.Object],System.Thread
ing.Tasks.Task]

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using System;
using System.Linq;
using System.Reactive.Linq;
using System.Windows.Forms;
using DictionarySuggest.DictionarySuggestService;
using System.Reactive;

namespace DictionarySuggest
{
    class Program

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namespace WebSocket

// Appache 2.0 license

// References:
// [1] Proposed WebSockets Spec December 2011         http://tools.ietf.org/html/rfc6455   
// [2] John McCutchan (Google Dart Team Member)       http://www.altdevblogaday.com/2012/01/23/writing-your-own-websocket-server/
// [3] A pretty good Python implemenation by mrrrgn   https://github.com/mrrrgn/websocket-data-frame-encoder-decoder/blob/master/frame.py
// [4] WebSockets Organising body                     http://www.websocket.org/echo.html
// [5] AndrewNewcomb's Gist (starting point)          https://gist.github.com/AndrewNewcomb/711664

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open Newtonsoft.Json

let serializerSettings = JsonSerializerSettings(ContractResolver = Serialization.CamelCasePropertyNamesContractResolver())
serializerSettings.Converters.Add(OptionConverter())

let serialize data =
    JsonConvert.SerializeObject(data, serializerSettings)
    |> Text.Encoding.UTF8.GetBytes

let deserialize<'T> (stream: Stream) =