Add dnd-character (#392)

Author: BNAndras

config.json

@@ -134,6 +134,14 @@
           "math"
         ]
       },
+      {
+        "slug": "dnd-character",
+        "name": "D&D Character",
+        "uuid": "79f913e1-9571-4b1e-81f5-f0f3160898cc",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 2
+      },
       {
         "slug": "eliuds-eggs",
         "name": "Eliud's Eggs",
@@ -458,10 +466,10 @@
         "practices": [],
         "prerequisites": [],
         "difficulty": 2,
+        "status": "deprecated",
         "topics": [
           "math"
-        ],
-        "status": "deprecated"
+        ]
       },
       {
         "slug": "two-fer",

exercises/practice/dnd-character/.docs/instructions.md

@@ -0,0 +1,32 @@
+# Instructions
+
+For a game of [Dungeons & Dragons][dnd], each player starts by generating a character they can play with.
+This character has, among other things, six abilities; strength, dexterity, constitution, intelligence, wisdom and charisma.
+These six abilities have scores that are determined randomly.
+You do this by rolling four 6-sided dice and recording the sum of the largest three dice.
+You do this six times, once for each ability.
+
+Your character's initial hitpoints are 10 + your character's constitution modifier.
+You find your character's constitution modifier by subtracting 10 from your character's constitution, divide by 2 and round down.
+
+Write a random character generator that follows the above rules.
+
+For example, the six throws of four dice may look like:
+
+- 5, 3, 1, 6: You discard the 1 and sum 5 + 3 + 6 = 14, which you assign to strength.
+- 3, 2, 5, 3: You discard the 2 and sum 3 + 5 + 3 = 11, which you assign to dexterity.
+- 1, 1, 1, 1: You discard the 1 and sum 1 + 1 + 1 = 3, which you assign to constitution.
+- 2, 1, 6, 6: You discard the 1 and sum 2 + 6 + 6 = 14, which you assign to intelligence.
+- 3, 5, 3, 4: You discard the 3 and sum 5 + 3 + 4 = 12, which you assign to wisdom.
+- 6, 6, 6, 6: You discard the 6 and sum 6 + 6 + 6 = 18, which you assign to charisma.
+
+Because constitution is 3, the constitution modifier is -4 and the hitpoints are 6.
+
+~~~~exercism/note
+Most programming languages feature (pseudo-)random generators, but few programming languages are designed to roll dice.
+One such language is [Troll][troll].
+
+[troll]: https://di.ku.dk/Ansatte/?pure=da%2Fpublications%2Ftroll-a-language-for-specifying-dicerolls(84a45ff0-068b-11df-825d-000ea68e967b)%2Fexport.html
+~~~~
+
+[dnd]: https://en.wikipedia.org/wiki/Dungeons_%26_Dragons

exercises/practice/dnd-character/.docs/introduction.md

@@ -0,0 +1,10 @@
+# Introduction
+
+After weeks of anticipation, you and your friends get together for your very first game of [Dungeons & Dragons][dnd] (D&D).
+Since this is the first session of the game, each player has to generate a character to play with.
+The character's abilities are determined by rolling 6-sided dice, but where _are_ the dice?
+With a shock, you realize that your friends are waiting for _you_ to produce the dice; after all it was your idea to play D&D!
+Panicking, you realize you forgot to bring the dice, which would mean no D&D game.
+As you have some basic coding skills, you quickly come up with a solution: you'll write a program to simulate dice rolls.
+
+[dnd]: https://en.wikipedia.org/wiki/Dungeons_%26_Dragons

exercises/practice/dnd-character/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "BNAndras"
+  ],
+  "files": {
+    "solution": [
+      "dnd-character.el"
+    ],
+    "test": [
+      "dnd-character-test.el"
+    ],
+    "example": [
+      ".meta/example.el"
+    ]
+  },
+  "blurb": "Randomly generate Dungeons & Dragons characters.",
+  "source": "Simon Shine, Erik Schierboom",
+  "source_url": "https://github.com/exercism/problem-specifications/issues/616#issuecomment-437358945"
+}

exercises/practice/dnd-character/.meta/example.el

@@ -0,0 +1,32 @@
+;;; dnd-character.el --- D&D Character (exercism)  -*- lexical-binding: t; -*-
+
+;;; Commentary:
+
+;;; Code:
+
+
+(defun modifier (score)
+  (floor (- score 10) 2))
+
+
+(defun ability ()
+  (let ((rolls '()))
+    (dotimes (i 4)
+      (push (+ 1 (random 6)) rolls))
+    (apply '+ (cdr (sort rolls '<)))))
+
+(defun generate-dnd-character ()
+   (let ((constitution (ability)))
+      (record 'dnd-character
+              (ability)                         ; strength
+              (ability)                         ; dexterity
+              constitution                      ; constitution
+              (ability)                         ; intelligence
+              (ability)                         ; wisdom
+              (ability)                         ; charisma
+              (+ 10 (modifier constitution))))) ; hitpoints
+
+
+(provide 'dnd-character)
+;;; dnd-character.el ends here
+

exercises/practice/dnd-character/.meta/tests.toml

@@ -0,0 +1,74 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[1e9ae1dc-35bd-43ba-aa08-e4b94c20fa37]
+description = "ability modifier -> ability modifier for score 3 is -4"
+
+[cc9bb24e-56b8-4e9e-989d-a0d1a29ebb9c]
+description = "ability modifier -> ability modifier for score 4 is -3"
+
+[5b519fcd-6946-41ee-91fe-34b4f9808326]
+description = "ability modifier -> ability modifier for score 5 is -3"
+
+[dc2913bd-6d7a-402e-b1e2-6d568b1cbe21]
+description = "ability modifier -> ability modifier for score 6 is -2"
+
+[099440f5-0d66-4b1a-8a10-8f3a03cc499f]
+description = "ability modifier -> ability modifier for score 7 is -2"
+
+[cfda6e5c-3489-42f0-b22b-4acb47084df0]
+description = "ability modifier -> ability modifier for score 8 is -1"
+
+[c70f0507-fa7e-4228-8463-858bfbba1754]
+description = "ability modifier -> ability modifier for score 9 is -1"
+
+[6f4e6c88-1cd9-46a0-92b8-db4a99b372f7]
+description = "ability modifier -> ability modifier for score 10 is 0"
+
+[e00d9e5c-63c8-413f-879d-cd9be9697097]
+description = "ability modifier -> ability modifier for score 11 is 0"
+
+[eea06f3c-8de0-45e7-9d9d-b8cab4179715]
+description = "ability modifier -> ability modifier for score 12 is +1"
+
+[9c51f6be-db72-4af7-92ac-b293a02c0dcd]
+description = "ability modifier -> ability modifier for score 13 is +1"
+
+[94053a5d-53b6-4efc-b669-a8b5098f7762]
+description = "ability modifier -> ability modifier for score 14 is +2"
+
+[8c33e7ca-3f9f-4820-8ab3-65f2c9e2f0e2]
+description = "ability modifier -> ability modifier for score 15 is +2"
+
+[c3ec871e-1791-44d0-b3cc-77e5fb4cd33d]
+description = "ability modifier -> ability modifier for score 16 is +3"
+
+[3d053cee-2888-4616-b9fd-602a3b1efff4]
+description = "ability modifier -> ability modifier for score 17 is +3"
+
+[bafd997a-e852-4e56-9f65-14b60261faee]
+description = "ability modifier -> ability modifier for score 18 is +4"
+
+[4f28f19c-2e47-4453-a46a-c0d365259c14]
+description = "random ability is within range"
+
+[385d7e72-864f-4e88-8279-81a7d75b04ad]
+description = "random character is valid"
+
+[2ca77b9b-c099-46c3-a02c-0d0f68ffa0fe]
+description = "each ability is only calculated once"
+include = false
+
+[dca2b2ec-f729-4551-84b9-078876bb4808]
+description = "each ability is only calculated once"
+reimplements = "2ca77b9b-c099-46c3-a02c-0d0f68ffa0fe"
+include = false
+

exercises/practice/dnd-character/dnd-character-test.el

@@ -0,0 +1,105 @@
+;;; dnd-character-test.el --- D&D Character (exercism)  -*- lexical-binding: t; -*-
+
+;;; Commentary:
+
+;;; Code:
+
+
+(load-file "dnd-character.el")
+(declare-function modifier "dnd-character.el" (score))
+(declare-function ability "dnd-character.el" ())
+(declare-function generate-dnd-character "dnd-character.el" ())
+
+
+(ert-deftest ability-modifier-for-score-3-is-negative-4 ()
+  (should (= -4 (modifier 3))))
+
+
+(ert-deftest ability-modifier-for-score-4-is-negative-3 ()
+  (should (= -3 (modifier 4))))
+
+
+(ert-deftest ability-modifier-for-score-5-is-negative-3 ()
+  (should (= -3 (modifier 5))))
+
+
+(ert-deftest ability-modifier-for-score-6-is-negative-2 ()
+  (should (= -2 (modifier 6))))
+
+
+(ert-deftest ability-modifier-for-score-7-is-negative-2 ()
+  (should (= -2 (modifier 7))))
+
+
+(ert-deftest ability-modifier-for-score-8-is-negative-1 ()
+  (should (= -1 (modifier 8))))
+
+
+(ert-deftest ability-modifier-for-score-9-is-negative-1 ()
+  (should (= -1 (modifier 9))))
+
+
+(ert-deftest ability-modifier-for-score-10-is-0 ()
+  (should (= 0 (modifier 10))))
+
+
+(ert-deftest ability-modifier-for-score-11-is-0 ()
+  (should (= 0 (modifier 11))))
+
+
+(ert-deftest ability-modifier-for-score-12-is-positive-1 ()
+  (should (= 1 (modifier 12))))
+
+
+(ert-deftest ability-modifier-for-score-13-is-positive-1 ()
+  (should (= 1 (modifier 13))))
+
+
+(ert-deftest ability-modifier-for-score-14-is-positive-2 ()
+  (should (= 2 (modifier 14))))
+
+
+(ert-deftest ability-modifier-for-score-15-is-positive-2 ()
+  (should (= 2 (modifier 15))))
+
+
+(ert-deftest ability-modifier-for-score-16-is-positive-3 ()
+  (should (= 3 (modifier 16))))
+
+
+(ert-deftest ability-modifier-for-score-17-is-positive-3 ()
+  (should (= 3 (modifier 17))))
+
+
+(ert-deftest ability-modifier-for-score-18-is-positive-4 ()
+  (should (= 4 (modifier 18))))
+
+
+(defun valid-range-p (score)
+  (and (<= 3 score) (>= 18 score)))
+
+(ert-deftest random-ability-is-within-range ()
+  (should (valid-range-p (ability))))
+
+
+(ert-deftest random-character-is-valid ()
+   (let* ((dnd-char (generate-dnd-character))
+          (strength (aref dnd-char 1))
+          (dexterity (aref dnd-char 2))
+          (constitution (aref dnd-char 3))
+          (intelligence (aref dnd-char 4))
+          (wisdom (aref dnd-char 5))
+          (charisma (aref dnd-char 6))
+          (hitpoints (aref dnd-char 7)))
+      (should (and (recordp dnd-char)
+                   (valid-range-p strength)
+                   (valid-range-p dexterity)
+                   (valid-range-p constitution)
+                   (valid-range-p intelligence)
+                   (valid-range-p wisdom)
+                   (valid-range-p charisma)))))
+
+
+(provide 'dnd-character-test)
+;;; dnd-character-test.el ends here
+

exercises/practice/dnd-character/dnd-character.el

@@ -0,0 +1,22 @@
+;;; dnd-character.el --- D&D Character (exercism)  -*- lexical-binding: t; -*-
+
+;;; Commentary:
+
+;;; Code:
+
+
+(defun modifier (score)
+  (error "Delete this S-Expression and write your own implementation"))
+
+
+(defun ability ()
+  (error "Delete this S-Expression and write your own implementation"))
+
+
+(defun generate-dnd-character ()
+  (error "Delete this S-Expression and write your own implementation"))
+
+
+(provide 'dnd-character)
+;;; dnd-character.el ends here
+