Some utilities & howto

Util.fs

module Util

open System
open System.Collections.Generic

let toGenericList lst = List<_>(List.toSeq lst)

let env = 
  let envVars = 
    Environment.GetEnvironmentVariables()
    |> Seq.cast<Collections.DictionaryEntry>
    |> Seq.map (fun d -> string d.Key, string d.Value)
    |> Map.ofSeq

  fun key -> Map.tryFind key envVars

let envDef key defVal = Option.defaultValue defVal (env key)

type OptionBuilder() =
    member x.Bind(v,f) = Option.bind f v
    member x.Return v = Some v
    member x.ReturnFrom o = o
    member x.Zero() = None

let opt = OptionBuilder()

let flip f x y = f y x