e | Male // Discriminated unions
type Person = { Name : string; Gender : Gender } // Records

module Stuff = // Modules
    type Foo() = // Classes
        let mutable bar = 0 // Fields
        member __.Set v = bar <- v * 10 // Members (instance & static)

let prettyPrint = function // Pattern matching & control flow
    | Male -> "gent"
    | Female -> "lady"

let xs = [|Male; Female|] // FSharp.Core data structures & functions
let ys = xs |> Array.sort // Structural comparison/equality

let foo x = async