From 43dde8dae34933dee1b4ebe3e001d54e8c02c189 Mon Sep 17 00:00:00 2001
From: meatball <meatballsofmeatballs@gmail.com>
Date: Thu, 10 Oct 2024 22:14:49 +0200
Subject: [PATCH] More work

---
 concepts/guards/.meta/config.json             |  6 ++++
 concepts/guards/about.md                      | 30 +++++++++++++++++++
 concepts/guards/introduction.md               | 30 +++++++++++++++++++
 concepts/guards/links.json                    |  1 +
 .../.meta/exemplar/src/GuessingGame.hs        | 13 ++++----
 5 files changed, 73 insertions(+), 7 deletions(-)
 create mode 100644 concepts/guards/.meta/config.json
 create mode 100644 concepts/guards/about.md
 create mode 100644 concepts/guards/introduction.md
 create mode 100644 concepts/guards/links.json

diff --git a/concepts/guards/.meta/config.json b/concepts/guards/.meta/config.json
new file mode 100644
index 000000000..7ffe8f6c1
--- /dev/null
+++ b/concepts/guards/.meta/config.json
@@ -0,0 +1,6 @@
+{
+  "authors": [
+    "meatball133"
+  ],
+  "blurb": "Guards are used to prevent function invocation based on evaluation of the arguments by guard functions. Guards begin with the `|` operatpr, followed by a boolean expression. Guards are used to augment pattern matching with more complex checks."
+}
diff --git a/concepts/guards/about.md b/concepts/guards/about.md
new file mode 100644
index 000000000..5893b3a54
--- /dev/null
+++ b/concepts/guards/about.md
@@ -0,0 +1,30 @@
+# About
+
+[Guards][guards] are used as a complement to [pattern matching][exercism-pattern-matching].
+Which we will cover in a later concept.
+Guards allows us to have different implementations of a function depending on the value of the input.
+They allow for more complex checks.
+
+A guard statement is defined by a pipe `|` followed by a boolean expression, ending with an equal sign `=` and the functions body.
+There can be multiple guard statements for a single function.
+The guard statements is evaluated from top to bottom, and the first one that evaluates to `True` will be executed.
+A guard statement allows for a `otherwise` statement, which is a catch-all for any value that doesn't match the previous guard statements.
+
+```haskell
+isEven :: Int -> String
+isEven n
+    | even n = "n is even"
+    | otherwise = "n is odd"
+```
+
+We can also deffine our function and use it inside the guard statement.
+
+```haskell
+isEven' :: Int -> Bool
+isEven' n = even n
+
+isEven :: Int -> String
+isEven n
+    | isEven' n = "n is even"
+    | otherwise = "n is odd"
+```
diff --git a/concepts/guards/introduction.md b/concepts/guards/introduction.md
new file mode 100644
index 000000000..5893b3a54
--- /dev/null
+++ b/concepts/guards/introduction.md
@@ -0,0 +1,30 @@
+# About
+
+[Guards][guards] are used as a complement to [pattern matching][exercism-pattern-matching].
+Which we will cover in a later concept.
+Guards allows us to have different implementations of a function depending on the value of the input.
+They allow for more complex checks.
+
+A guard statement is defined by a pipe `|` followed by a boolean expression, ending with an equal sign `=` and the functions body.
+There can be multiple guard statements for a single function.
+The guard statements is evaluated from top to bottom, and the first one that evaluates to `True` will be executed.
+A guard statement allows for a `otherwise` statement, which is a catch-all for any value that doesn't match the previous guard statements.
+
+```haskell
+isEven :: Int -> String
+isEven n
+    | even n = "n is even"
+    | otherwise = "n is odd"
+```
+
+We can also deffine our function and use it inside the guard statement.
+
+```haskell
+isEven' :: Int -> Bool
+isEven' n = even n
+
+isEven :: Int -> String
+isEven n
+    | isEven' n = "n is even"
+    | otherwise = "n is odd"
+```
diff --git a/concepts/guards/links.json b/concepts/guards/links.json
new file mode 100644
index 000000000..fe51488c7
--- /dev/null
+++ b/concepts/guards/links.json
@@ -0,0 +1 @@
+[]
diff --git a/exercises/concept/guessing-game/.meta/exemplar/src/GuessingGame.hs b/exercises/concept/guessing-game/.meta/exemplar/src/GuessingGame.hs
index 9f0c96d05..b111a9e23 100644
--- a/exercises/concept/guessing-game/.meta/exemplar/src/GuessingGame.hs
+++ b/exercises/concept/guessing-game/.meta/exemplar/src/GuessingGame.hs
@@ -1,9 +1,8 @@
 module GuessingGame (reply) where
 
-reply :: Int -> String
-reply 41 = "So close"
-reply 42 = "Correct"
-reply 43 = "So close"
-reply guess
-  | guess < 41 = "Too low"
-  | otherwise = "Too high"
+reply :: Int -> Int -> String
+reply n guess
+  | guess == n = "Correct"
+  | guess + 1 == n || guess - 1 == n = "So close!"
+  | guess < n = "Too low"
+  | guess > n = "Too high"