Add wordy (#487)

Author: keiravillekode

config.json

@@ -955,6 +955,14 @@
         "prerequisites": [],
         "difficulty": 6
       },
+      {
+        "slug": "wordy",
+        "name": "Wordy",
+        "uuid": "4aab08ad-7c41-427c-966e-cd90f4dc7ba5",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 6
+      },
       {
         "slug": "dominoes",
         "name": "Dominoes",

exercises/practice/wordy/.docs/instructions.md

@@ -0,0 +1,59 @@
+# Instructions
+
+Parse and evaluate simple math word problems returning the answer as an integer.
+
+## Iteration 0 — Numbers
+
+Problems with no operations simply evaluate to the number given.
+
+> What is 5?
+
+Evaluates to 5.
+
+## Iteration 1 — Addition
+
+Add two numbers together.
+
+> What is 5 plus 13?
+
+Evaluates to 18.
+
+Handle large numbers and negative numbers.
+
+## Iteration 2 — Subtraction, Multiplication and Division
+
+Now, perform the other three operations.
+
+> What is 7 minus 5?
+
+2
+
+> What is 6 multiplied by 4?
+
+24
+
+> What is 25 divided by 5?
+
+5
+
+## Iteration 3 — Multiple Operations
+
+Handle a set of operations, in sequence.
+
+Since these are verbal word problems, evaluate the expression from left-to-right, _ignoring the typical order of operations._
+
+> What is 5 plus 13 plus 6?
+
+24
+
+> What is 3 plus 2 multiplied by 3?
+
+15 (i.e. not 9)
+
+## Iteration 4 — Errors
+
+The parser should reject:
+
+- Unsupported operations ("What is 52 cubed?")
+- Non-math questions ("Who is the President of the United States")
+- Word problems with invalid syntax ("What is 1 plus plus 2?")

exercises/practice/wordy/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "keiravillekode"
+  ],
+  "files": {
+    "solution": [
+      "wordy.el"
+    ],
+    "test": [
+      "wordy-test.el"
+    ],
+    "example": [
+      ".meta/example.el"
+    ]
+  },
+  "blurb": "Parse and evaluate simple math word problems returning the answer as an integer.",
+  "source": "Inspired by one of the generated questions in the Extreme Startup game.",
+  "source_url": "https://github.com/rchatley/extreme_startup"
+}

exercises/practice/wordy/.meta/example.el

@@ -0,0 +1,31 @@
+;;; wordy.el --- Wordy (exercism)  -*- lexical-binding: t; -*-
+
+;;; Commentary:
+
+;;; Code:
+
+(define-error 'parse-error "unable to understand question")
+
+(defun calculate (left tokens)
+  (if (null tokens)
+    left
+    (let ((operation (car tokens)))
+      (cond
+        ((null (cdr tokens)) (signal 'parse-error nil))
+        ((string= operation "plus") (calculate (+ left (string-to-number (cadr tokens))) (drop 2 tokens)))
+        ((string= operation "minus") (calculate (- left (string-to-number (cadr tokens))) (drop 2 tokens)))
+        ((string= operation "multiplied-by") (calculate (* left (string-to-number (cadr tokens))) (drop 2 tokens)))
+        ((string= operation "divided-by") (calculate (/ left (string-to-number (cadr tokens))) (drop 2 tokens)))
+        (t (signal 'parse-error nil))))))
+
+(defun answer (question)
+  (unless (string= (substring question -1) "?") (signal 'parse-error nil))
+  (let ((tokens (split-string (string-replace " by" "-by" (substring question 0 -1)))))
+    (unless (string= (car tokens) "What") (signal 'parse-error nil))
+    (unless (string= (cadr tokens) "is") (signal 'parse-error nil))
+    (unless (cddr tokens) (signal 'parse-error nil))
+    (calculate (string-to-number (caddr tokens)) (drop 3 tokens))))
+
+
+(provide 'wordy)
+;;; wordy.el ends here

exercises/practice/wordy/.meta/tests.toml

@@ -0,0 +1,91 @@
+# 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.
+
+[88bf4b28-0de3-4883-93c7-db1b14aa806e]
+description = "just a number"
+
+[18983214-1dfc-4ebd-ac77-c110dde699ce]
+description = "just a zero"
+
+[607c08ee-2241-4288-916d-dae5455c87e6]
+description = "just a negative number"
+
+[bb8c655c-cf42-4dfc-90e0-152fcfd8d4e0]
+description = "addition"
+
+[bb9f2082-171c-46ad-ad4e-c3f72087c1b5]
+description = "addition with a left hand zero"
+
+[6fa05f17-405a-4742-80ae-5d1a8edb0d5d]
+description = "addition with a right hand zero"
+
+[79e49e06-c5ae-40aa-a352-7a3a01f70015]
+description = "more addition"
+
+[b345dbe0-f733-44e1-863c-5ae3568f3803]
+description = "addition with negative numbers"
+
+[cd070f39-c4cc-45c4-97fb-1be5e5846f87]
+description = "large addition"
+
+[0d86474a-cd93-4649-a4fa-f6109a011191]
+description = "subtraction"
+
+[30bc8395-5500-4712-a0cf-1d788a529be5]
+description = "multiplication"
+
+[34c36b08-8605-4217-bb57-9a01472c427f]
+description = "division"
+
+[da6d2ce4-fb94-4d26-8f5f-b078adad0596]
+description = "multiple additions"
+
+[7fd74c50-9911-4597-be09-8de7f2fea2bb]
+description = "addition and subtraction"
+
+[b120ffd5-bad6-4e22-81c8-5512e8faf905]
+description = "multiple subtraction"
+
+[4f4a5749-ef0c-4f60-841f-abcfaf05d2ae]
+description = "subtraction then addition"
+
+[312d908c-f68f-42c9-aa75-961623cc033f]
+description = "multiple multiplication"
+
+[38e33587-8940-4cc1-bc28-bfd7e3966276]
+description = "addition and multiplication"
+
+[3c854f97-9311-46e8-b574-92b60d17d394]
+description = "multiple division"
+
+[3ad3e433-8af7-41ec-aa9b-97b42ab49357]
+description = "unknown operation"
+
+[8a7e85a8-9e7b-4d46-868f-6d759f4648f8]
+description = "Non math question"
+
+[42d78b5f-dbd7-4cdb-8b30-00f794bb24cf]
+description = "reject problem missing an operand"
+
+[c2c3cbfc-1a72-42f2-b597-246e617e66f5]
+description = "reject problem with no operands or operators"
+
+[4b3df66d-6ed5-4c95-a0a1-d38891fbdab6]
+description = "reject two operations in a row"
+
+[6abd7a50-75b4-4665-aa33-2030fd08bab1]
+description = "reject two numbers in a row"
+
+[10a56c22-e0aa-405f-b1d2-c642d9c4c9de]
+description = "reject postfix notation"
+
+[0035bc63-ac43-4bb5-ad6d-e8651b7d954e]
+description = "reject prefix notation"

exercises/practice/wordy/wordy-test.el

@@ -0,0 +1,124 @@
+;;; wordy-test.el --- Tests for Wordy (exercism)  -*- lexical-binding: t; -*-
+
+;;; Commentary:
+
+;; For this exercise we don't require specific error strings,
+;; to avoid constraining solution approaches.
+
+;;; Code:
+
+
+(load-file "wordy.el")
+(declare-function answer "wordy.el" (question))
+
+
+(ert-deftest just-a-number ()
+  (should (= 5 (answer "What is 5?"))))
+
+
+(ert-deftest just-a-zero ()
+  (should (= 0 (answer "What is 0?"))))
+
+
+(ert-deftest just-a-negative-number ()
+  (should (= -123 (answer "What is -123?"))))
+
+
+(ert-deftest addition ()
+  (should (= 2 (answer "What is 1 plus 1?"))))
+
+
+(ert-deftest addition-with-a-left-hand-zero ()
+  (should (= 2 (answer "What is 0 plus 2?"))))
+
+
+(ert-deftest addition-with-a-right-hand-zero ()
+  (should (= 3 (answer "What is 3 plus 0?"))))
+
+
+(ert-deftest more-addition ()
+  (should (= 55 (answer "What is 53 plus 2?"))))
+
+
+(ert-deftest addition-with-negative-numbers ()
+  (should (= -11 (answer "What is -1 plus -10?"))))
+
+
+(ert-deftest large-addition ()
+  (should (= 45801 (answer "What is 123 plus 45678?"))))
+
+
+(ert-deftest subtraction ()
+  (should (= 16 (answer "What is 4 minus -12?"))))
+
+
+(ert-deftest multiplication ()
+  (should (= -75 (answer "What is -3 multiplied by 25?"))))
+
+
+(ert-deftest division ()
+  (should (= -11 (answer "What is 33 divided by -3?"))))
+
+
+(ert-deftest multiple-additions ()
+  (should (= 3 (answer "What is 1 plus 1 plus 1?"))))
+
+
+(ert-deftest addition-and-subtraction ()
+  (should (= 8 (answer "What is 1 plus 5 minus -2?"))))
+
+
+(ert-deftest multiple-subtraction ()
+  (should (= 3 (answer "What is 20 minus 4 minus 13?"))))
+
+
+(ert-deftest subtraction-then-addition ()
+  (should (= 14 (answer "What is 17 minus 6 plus 3?"))))
+
+
+(ert-deftest multiple-multiplication ()
+  (should (= -12 (answer "What is 2 multiplied by -2 multiplied by 3?"))))
+
+
+(ert-deftest addition-and-multiplication ()
+  (should (= -8 (answer "What is -3 plus 7 multiplied by -2?"))))
+
+
+(ert-deftest multiple-division ()
+  (should (= 2 (answer "What is -12 divided by 2 divided by -3?"))))
+
+
+(ert-deftest unknown-operation ()
+  (should-error (answer "What is 52 cubed?") :type 'parse-error))
+
+
+(ert-deftest non-math-question ()
+  (should-error (answer "Who is the President of the United States?") :type 'parse-error))
+
+
+(ert-deftest reject-problem-missing-an-operand ()
+  (should-error (answer "What is 1 plus?") :type 'parse-error))
+
+
+(ert-deftest reject-problem-with-no-operands-or-operators ()
+  (should-error (answer "What is?") :type 'parse-error))
+
+
+(ert-deftest reject-two-operations-in-a-row ()
+  (should-error (answer "What is 1 plus plus 2?") :type 'parse-error))
+
+
+(ert-deftest reject-two-numbers-in-a-row ()
+  (should-error (answer "What is 1 plus 2 1?") :type 'parse-error))
+
+
+(ert-deftest reject-postfix-notation ()
+  (should-error (answer "What is 1 2 plus?") :type 'parse-error))
+
+
+(ert-deftest reject-prefix-notation ()
+  (should-error (answer "What is plus 1 2?") :type 'parse-error))
+
+
+(provide 'wordy-test)
+;;; wordy-test.el ends here

exercises/practice/wordy/wordy.el

@@ -0,0 +1,17 @@
+;;; wordy.el --- Wordy (exercism)  -*- lexical-binding: t; -*-
+
+;;; Commentary:
+
+;;; Code:
+
+
+(define-error 'parse-error
+              (error "Delete this S-Expression and write your own implementation"))
+
+
+(defun answer (question)
+  (error "Delete this S-Expression and write your own implementation"))
+
+
+(provide 'wordy)
+;;; wordy.el ends here