Add better burgers chapter

docs/.vitepress/config.js

@@ -37,6 +37,7 @@ export default defineConfig({
           { text: 'Order Confirmation', link: '/order-confirmation/' },
           { text: 'Styling with CSS', link: '/styling-with-css/' },
           { text: 'Better Sandwiches', link: '/better-sandwiches/' },
+          { text: 'Better Burgers', link: '/better-burgers/' },
         ]
       }
     ],

docs/better-burgers/Item.re

@@ -0,0 +1,389 @@
+module ItemV1 = {
+  // #region starting-item-t
+  type sandwich =
+    | Portabello
+    | Ham
+    | Unicorn
+    | Turducken;
+
+  type t =
+    | Sandwich(sandwich)
+    | Burger
+    | Hotdog;
+  // #endregion starting-item-t
+};
+
+module ItemV2 = {
+  type sandwich =
+    | Portabello
+    | Ham
+    | Unicorn
+    | Turducken;
+
+  // #region add-burger-type
+  type burger = {
+    lettuce: bool,
+    onions: int,
+    cheese: int,
+  };
+
+  type t =
+    | Sandwich(sandwich)
+    | Burger(burger)
+    | Hotdog;
+  // #endregion add-burger-type
+
+  // #region to-emoji
+  let toEmoji =
+    fun
+    | Hotdog => {js|🌭|js}
+    | Sandwich(sandwich) =>
+      Printf.sprintf(
+        {js|🥪(%s)|js},
+        switch (sandwich) {
+        | Portabello => {js|🍄|js}
+        | Ham => {js|🐷|js}
+        | Unicorn => {js|🦄|js}
+        | Turducken => {js|🦃🦆🐓|js}
+        },
+      )
+    | Burger(burger) =>
+      Printf.sprintf(
+        {js|🍔{%s}|js},
+        [|
+          burger.lettuce ? {js|🥬|js} : "",
+          {js|🧅×|js} ++ string_of_int(burger.onions),
+          {js|🧀×|js} ++ string_of_int(burger.cheese),
+        |]
+        |> Js.Array.filter(str => str != "")
+        |> Js.Array.joinWith(", "),
+      );
+  // #endregion to-emoji
+
+  let toEmojiBurgerDestructure =
+    fun
+    | Hotdog
+    | Sandwich(_) => "fake"
+    // #region destructure-burger
+    | Burger(burger) => {
+        let {lettuce, onions, cheese} = burger;
+        Printf.sprintf(
+          {js|🍔{%s}|js},
+          [|
+            lettuce ? {js|🥬|js} : "",
+            {js|🧅×|js} ++ string_of_int(onions),
+            {js|🧀×|js} ++ string_of_int(cheese),
+          |]
+          |> Js.Array.filter(str => str != "")
+          |> Js.Array.joinWith(", "),
+        );
+      };
+  // #endregion destructure-burger
+
+  let toEmojiBurgerDestructureBranch =
+    fun
+    | Hotdog
+    | Sandwich(_) => "fake"
+    // #region destructure-burger-branch
+    | Burger({lettuce, onions, cheese}) =>
+      Printf.sprintf(
+        {js|🍔{%s}|js},
+        [|
+          lettuce ? {js|🥬|js} : "",
+          {js|🧅×|js} ++ string_of_int(onions),
+          {js|🧀×|js} ++ string_of_int(cheese),
+        |]
+        |> Js.Array.filter(str => str != "")
+        |> Js.Array.joinWith(", "),
+      );
+  // #endregion destructure-burger-branch
+
+  let toEmojiBurgerMultiple =
+    fun
+    | Hotdog
+    | Sandwich(_) => "fake"
+    // #region multiple
+    | Burger({lettuce, onions, cheese}) => {
+        let multiple = (emoji, count) =>
+          Printf.sprintf({js|%s×%d|js}, emoji, count);
+
+        Printf.sprintf(
+          {js|🍔{%s}|js},
+          [|
+            lettuce ? {js|🥬|js} : "",
+            multiple({js|🧅|js}, onions),
+            multiple({js|🧀|js}, cheese),
+          |]
+          |> Js.Array.filter(str => str != "")
+          |> Js.Array.joinWith(", "),
+        );
+      };
+  // #endregion multiple
+};
+
+module ItemV3 = {
+  // #region burger-submodule
+  module Burger = {
+    type t = {
+      lettuce: bool,
+      onions: int,
+      cheese: int,
+    };
+
+    let toEmoji = ({lettuce, onions, cheese}) => {
+      let multiple = (emoji, count) =>
+        Printf.sprintf({js|%s×%d|js}, emoji, count);
+
+      Printf.sprintf(
+        {js|🍔{%s}|js},
+        [|
+          lettuce ? {js|🥬|js} : "",
+          multiple({js|🧅|js}, onions),
+          multiple({js|🧀|js}, cheese),
+        |]
+        |> Js.Array.filter(str => str != "")
+        |> Js.Array.joinWith(", "),
+      );
+    };
+
+    let toPrice = _burger => 15.;
+  };
+  // #endregion burger-submodule
+
+  type sandwich =
+    | Portabello
+    | Ham
+    | Unicorn
+    | Turducken;
+
+  // #region t-and-functions
+  type t =
+    | Sandwich(sandwich)
+    | Burger(Burger.t)
+    | Hotdog;
+
+  let toEmoji =
+    fun
+    | Hotdog => {js|🌭|js}
+    | Burger(burger) => Burger.toEmoji(burger)
+    | Sandwich(sandwich) =>
+      Printf.sprintf(
+        {js|🥪(%s)|js},
+        switch (sandwich) {
+        | Portabello => {js|🍄|js}
+        | Ham => {js|🐷|js}
+        | Unicorn => {js|🦄|js}
+        | Turducken => {js|🦃🦆🐓|js}
+        },
+      );
+
+  let toPrice = t => {
+    let day = Js.Date.make() |> Js.Date.getDay |> int_of_float;
+
+    switch (t) {
+    | Sandwich(Portabello | Ham) => 10.
+    | Sandwich(Unicorn) => 80.
+    | Sandwich(Turducken) when day == 2 => 10.
+    | Sandwich(Turducken) => 20.
+    | Burger(burger) => Burger.toPrice(burger)
+    | Hotdog => 5.
+    };
+  };
+  // #endregion t-and-functions
+
+  module BurgerFunctions = {
+    type t = {
+      lettuce: bool,
+      onions: int,
+      cheese: int,
+    };
+
+    // #region record-wildcard
+    let toPrice = ({onions, cheese, _}) =>
+      15.  // base cost
+      +. float_of_int(onions)
+      *. 0.2
+      +. float_of_int(cheese)
+      *. 0.1;
+    // #endregion record-wildcard
+
+    toPrice({lettuce: false, onions: 0, cheese: 0}) |> ignore;
+
+    // #region record-lettuce-wildcard
+    let toPrice = ({onions, cheese, lettuce: _}) =>
+      15.  // base cost
+      +. float_of_int(onions)
+      *. 0.2
+      +. float_of_int(cheese)
+      *. 0.1;
+    // #endregion record-lettuce-wildcard
+
+    // #region ternary
+    let toEmoji = ({lettuce, onions, cheese}) => {
+      let multiple = (emoji, count) =>
+        Printf.sprintf({js|%s×%d|js}, emoji, count);
+
+      !lettuce && onions == 0 && cheese == 0
+        ? {js|🍔|js}
+        : Printf.sprintf(
+            {js|🍔{%s}|js},
+            [|
+              lettuce ? {js|🥬|js} : "",
+              multiple({js|🧅|js}, onions),
+              multiple({js|🧀|js}, cheese),
+            |]
+            |> Js.Array.filter(str => str != "")
+            |> Js.Array.joinWith(", "),
+          );
+    };
+    // #endregion ternary
+
+    toEmoji({lettuce: false, onions: 0, cheese: 0}) |> ignore;
+
+    // #region match-tuple
+    let toEmoji = ({lettuce, onions, cheese}) => {
+      let multiple = (emoji, count) =>
+        Printf.sprintf({js|%s×%d|js}, emoji, count);
+
+      switch (lettuce, onions, cheese) {
+      | (false, 0, 0) => {js|🍔|js}
+      | (lettuce, onions, cheese) =>
+        Printf.sprintf(
+          {js|🍔{%s}|js},
+          [|
+            lettuce ? {js|🥬|js} : "",
+            multiple({js|🧅|js}, onions),
+            multiple({js|🧀|js}, cheese),
+          |]
+          |> Js.Array.filter(str => str != "")
+          |> Js.Array.joinWith(", "),
+        )
+      };
+    };
+    // #endregion match-tuple
+
+    toEmoji({lettuce: false, onions: 0, cheese: 0}) |> ignore;
+
+    // #region match-record
+    let toEmoji = t => {
+      let multiple = (emoji, count) =>
+        Printf.sprintf({js|%s×%d|js}, emoji, count);
+
+      switch (t) {
+      | {lettuce: false, onions: 0, cheese: 0} => {js|🍔|js}
+      | {lettuce, onions, cheese} =>
+        Printf.sprintf(
+          {js|🍔{%s}|js},
+          [|
+            lettuce ? {js|🥬|js} : "",
+            multiple({js|🧅|js}, onions),
+            multiple({js|🧀|js}, cheese),
+          |]
+          |> Js.Array.filter(str => str != "")
+          |> Js.Array.joinWith(", "),
+        )
+      };
+    };
+    // #endregion match-record
+  };
+};
+
+// #region sandwich-module
+module Sandwich = {
+  type t =
+    | Portabello
+    | Ham
+    | Unicorn
+    | Turducken;
+
+  let toPrice = t => {
+    let day = Js.Date.make() |> Js.Date.getDay |> int_of_float;
+
+    switch (t) {
+    | Portabello
+    | Ham => 10.
+    | Unicorn => 80.
+    | Turducken when day == 2 => 10.
+    | Turducken => 20.
+    };
+  };
+
+  let toEmoji = t =>
+    Printf.sprintf(
+      {js|🥪(%s)|js},
+      switch (t) {
+      | Portabello => {js|🍄|js}
+      | Ham => {js|🐷|js}
+      | Unicorn => {js|🦄|js}
+      | Turducken => {js|🦃🦆🐓|js}
+      },
+    );
+};
+// #endregion sandwich-module
+
+module BurgerTomatoBacon = {
+  // #region to-price-tomato-bacon
+  type t = {
+    lettuce: bool,
+    onions: int,
+    cheese: int,
+    tomatoes: bool,
+    bacon: int,
+  };
+
+  let toPrice = ({onions, cheese, tomatoes, bacon, lettuce: _}) =>
+    15.  // base cost
+    +. float_of_int(onions)
+    *. 0.2
+    +. float_of_int(cheese)
+    *. 0.1
+    +. (tomatoes ? 0.05 : 0.0)
+    +. float_of_int(bacon)
+    *. 0.5;
+  // #endregion to-price-tomato-bacon
+
+  toPrice({lettuce: false, onions: 0, cheese: 0, tomatoes: false, bacon: 0})
+  |> ignore;
+
+  // #region to-price-topping-cost
+  let toPrice = ({onions, cheese, tomatoes, bacon, lettuce: _}) => {
+    let toppingCost = (quantity, cost) => float_of_int(quantity) *. cost;
+
+    15.  // base cost
+    +. toppingCost(onions, 0.2)
+    +. toppingCost(cheese, 0.1)
+    +. (tomatoes ? 0.05 : 0.0)
+    +. toppingCost(bacon, 0.5);
+  };
+  // #endregion to-price-topping-cost
+
+  // #region to-emoji-multiple
+  let multiple = (emoji, count) =>
+    switch (count) {
+    | 0 => ""
+    | 1 => emoji
+    | count => Printf.sprintf({js|%s×%d|js}, emoji, count)
+    };
+  // #endregion to-emoji-multiple
+
+  multiple("", 0) |> ignore;
+
+  // #region to-emoji-multiple-fun
+  let multiple = emoji =>
+    fun
+    | 0 => ""
+    | 1 => emoji
+    | count => Printf.sprintf({js|%s×%d|js}, emoji, count);
+  // #endregion to-emoji-multiple-fun
+
+  multiple("", 0) |> ignore;
+
+  // #region to-emoji-multiple-fun-annotated
+  let multiple: (string, int) => string =
+    emoji =>
+      fun
+      | 0 => ""
+      | 1 => emoji
+      | count => Printf.sprintf({js|%s×%d|js}, emoji, count);
+  // #endregion to-emoji-multiple-fun-annotated
+};