habib-sadullaev

type Tuple = Tuple with
    static member inline TupleMap (Tuple, (a, b)) = fun f -> (f a, f b)
    static member inline TupleMap (Tuple, (a, b, c)) = fun f -> (f a, f b, f c)
    static member inline TupleMap (Tuple, (a, b, c, d)) = fun f -> (f a, f b, f c, f d)

let inline mapTuple f x =
    let inline map (a: ^a) (b : ^b) = ((^a or ^b) : (static member TupleMap : ^a * ^b -> ^t) (a, b))
    map Tuple x f

mapTuple (fun x -> x * x + 1) (1, 2)

habib-sadullaev

open System
open System.Runtime.CompilerServices

[<Extension>]
type X =
    [<Extension>]
    static member Bind(_: OptionBuilder, v: 'a, f: 'a -> 'b option) =
        match box v with
        | null -> None
        | :? string as v when String.IsNullOrEmpty v -> None

habib-sadullaev

let traverse (exprs: Expr<'a> list) =
    let folder elem state = <@ %elem :: %state @>
    let init = <@ [] @>
    List.foldBack folder exprs init

[1..3] |> List.map (fun x -> <@ x @>) |> traverse

habib-sadullaev

open FSharp.Quotations
open FSharp.Linq.RuntimeHelpers
open System.Linq
open System

type AST =
    | StartsWith of string
    | Contains of string
    | EndsWith of string

habib-sadullaev

//fsharplint:disable
type M<'a> = 'a option
let inline unit (x: 'a) : M<'a> = Some x
let inline (>>=) (x: M<'a>) (f: 'a -> M<'b>) : M<'b> = 
    x |> Option.bind f

type MonadBuilder() =
    member _.Bind(mx: M<'a>, f: 'a -> M<'b>) = mx >>= f
    member _.Return(x: 'a) = unit x
    member _.ReturnFrom(mx : M<'a>) = mx

habib-sadullaev

open System.Runtime.InteropServices

type C1() = static member M([<Out>] arg: byref<C1>) = arg <- C1(); true // byref<C1> -> bool
type C2() = static member M(arg: byref<C2>) = arg <- C2(); true // byref<C2> -> bool
type C3() = static member M(arg: outref<C3>) = arg <- C3(); true // outref<C3> -> bool

C1.M // val it : unit -> bool * C1
C2.M // val it : C2 ref -> bool
C3.M // val it : unit -> bool * C2

habib-sadullaev

#lang racket
(define (make-deque) (mcons null null))

(define (front deque) (mcar deque))
(define (rear deque) (mcdr deque))

(define (set-front! deque item) (set-mcar! deque item))
(define (set-rear! deque item) (set-mcdr! deque item))

(define (empty? deque) (null? (front deque)))