dogwith1eye

using System;
using QueryPattern.Test1;
using QueryPattern.Test2;
using LaYumba.Functional;

namespace QueryPattern
{
	using System.Threading.Tasks;
	using static Console;
	using static F;

dogwith1eye

using System;
using System.Threading.Tasks;
using LaYumba.Functional;

namespace QueryPattern
{
	using static Console;
	using static F;
	class Program
	{

dogwith1eye

// IMPORTANT! Learn this when teaching yourself f#

// BAD! Encourages a non functional request/response design
class MyParametricApi
{
    public MyParametricApi(IDep1 dep1, IDep2 dep2, IDep3 dep3) {}
    public string Function1(int arg1) { ... }
    public string Function2(string arg2) { ... }
}

dogwith1eye

let context = 
      { Dep1 = CON ".\SqlExpress";
        Dep2 = ENV "DEP_2";
        Dep3 = RND (System.Random().Next()); }

let app2 = (function2 "test" 
                >>=. function1 
                >>-  function4 
                >>=  (function3 >=> function2))

dogwith1eye

type Reader<'x> = Reader of 'x

module Reader =
    
    let pure x = Reader x
    
    let run xR ctx =  
        match xR with
        | Reader x -> x ctx

dogwith1eye

type ConnectionString = CON of string
type EnvVariable = ENV of string
type RandomNum = RND of int

type MyApiContext = 
  { Dep1 : ConnectionString ; 
    Dep2 : EnvVariable;
    Dep3 : RandomNum }

type MyApiPart<'a> = Reader<MyApiContext -> 'a>

dogwith1eye

let config = "world"
let greeter =
    pure (fun config -> "hello" + config + "!")
let calc (s:string) =
    pure (fun (config:string) -> s.Length - config.Length)
let app1 = (greeter >>= calc)
let r1 = run app1 config

dogwith1eye

type Reader<'x> = Reader of 'x

module Reader =
    
    let pure x = Reader x
    
    let run xR ctx =  
        match xR with
        | Reader x -> x ctx

dogwith1eye

type MyParametricApi(dep1, dep2, dep3) =
    let doStuffWith dep1 dep2 dep3 arg1 = printfn "stuff:%A" arg1
    let doStuffWith' dep1 dep2 dep3 arg2 = printfn "'stuff:%A" arg2
    member __.Function1 arg1 = doStuffWith dep1 dep2 dep3 arg1
    member __.Function2 arg2 = doStuffWith' dep1 dep2 dep3 arg2

dogwith1eye

interface IShowable<T>
{
    T Value { get; }
    U Accept<U>(IVisitor<T, U> visitor);
}

class ShowVisitor : IVisitor<string, string>,
                    IVisitor<int, string>,
                    IVisitor<float, string>
{