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// I've seen some examples of how JS promises fail Functor's composition law
// (by hijacking the `then` field of any JS object), making promises not valid
// functors (and by extension, unlawful monads), but I don't recall seeing a
// concise example of Promise breaking Monad's left identity law (though I'm
// sure this has been demonstrated somewhere before).
//
// The key here is that `return a` doesn't behave as expected when `a` is
// already a promise, due to the auto-collapsing nature of promises.

// Left Identity:

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module Face = {
  [@deriving (enum, ord, eq)]
  type t =
    | Blank
    | One
    | Two
    | Three
    | Four
    | Five
    | Six

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module Measurement = {
  type t =
    | Tsp
    | Tbsp
    | Cup
    | Ounce;
};

module Ingredient = {
  type t = {name: string};

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module AudioDestinationNode = {
  type t;
};

module OscillatorNode = {
  type t;
  
  [@bs.send]
  external connect: (t, AudioDestinationNode.t) => unit = "connect";
};

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module Main where

import Prelude

import Data.List (List(..), (:), fromFoldable, sortBy, reverse)

data Task = Task String Int

sortTasksByWeightDesc :: List Task -> List Task
sortTasksByWeightDesc = sortBy compareEffort >>> reverse where

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let const = (a, _) => a;
let (<<) = (f, g, a) => f(g(a));

module type Type = {type t;};

module Function1 = {
  type t('input, 'output) = 'input => 'output;
};

module type Functor = {

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// Generated by BUCKLESCRIPT, PLEASE EDIT WITH CARE
'use strict';

var List$Modules = require("./List.bs.js");
var String$Modules = require("./String.bs.js");

var x = List$Modules.contains(String$Modules.Eq, "a", /* :: */[
      "b",
      /* :: */[
        "c",

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// Generated by BUCKLESCRIPT, PLEASE EDIT WITH CARE
'use strict';

var ReludeRandom_Seed = require("./ReludeRandom_Seed.bs.js");
var ReludeRandom_Generator = require("./ReludeRandom_Generator.bs.js");
var ReludeRandom_RandomInt = require("./ReludeRandom_RandomInt.bs.js");
var ReludeRandom_RandomList = require("./ReludeRandom_RandomList.bs.js");

var Seed = {
  fromInt: ReludeRandom_Seed.fromInt,

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open Relude.Globals;

let baseUrl = "http://localhost:5050";

// `getForecast` is an IO that will either succeed with decoded
// ForecastData or fail with a Fetch error.
// 
// Since IO is inherently lazy, creating this value doesn't actually
// _do_ anything. Instead it needs to be run, which we do inside an
// `UpdateWithIO` return from a `useReducer` branch in our view.

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module type Monad  =
  sig
    type 'a t
    val map : ('a -> 'b) -> 'a t -> 'b t
    val apply : ('a -> 'b) t -> 'a t -> 'b t
    val pure : 'a -> 'a t
    val bind : 'a t -> ('a -> 'b t) -> 'b t
  end

module Option : Monad with type 'a t = 'a option = struct