Add wordy (#153)

Author: glennj

config.json

@@ -850,6 +850,14 @@
         "prerequisites": [],
         "difficulty": 6
       },
+      {
+        "slug": "wordy",
+        "name": "Wordy",
+        "uuid": "c4112228-adec-4109-a9aa-5bd366c1e658",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 6
+      },
       {
         "slug": "book-store",
         "name": "Book Store",

exercises/practice/wordy/.busted

@@ -0,0 +1,5 @@
+return {
+  default = {
+    ROOT = { '.' }
+  }
+}

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": [
+    "glennj"
+  ],
+  "files": {
+    "solution": [
+      "wordy.moon"
+    ],
+    "test": [
+      "wordy_spec.moon"
+    ],
+    "example": [
+      ".meta/example.moon"
+    ]
+  },
+  "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.moon

@@ -0,0 +1,49 @@
+re = require 're'       -- https://www.inf.puc-rio.br/~roberto/lpeg/re.html
+
+local err, evaluate
+
+answer = (input) ->
+  wordy = re.compile [[
+    wordy <- 'What is ' {| expr |} '?'
+    expr <- { num } (s {~ op ~} s { num })*
+    num <- '-'? %d+
+    op <- 'plus' -> '+'
+        / 'minus' -> '-'
+        / 'multiplied by' -> '*'
+        / 'divided by' -> '/'
+    s <- %s+
+  ]]
+
+  tokens = re.match input, wordy
+  if tokens
+    evaluate tokens
+  else
+    err input
+
+evaluate = (tokens) ->
+  result = tonumber tokens[1]
+  for i = 2, #tokens, 2
+    addend = tonumber tokens[i+1]
+    result = switch tokens[i]
+      when '+' then result + addend
+      when '-' then result - addend
+      when '*' then result * addend
+      when '/' then result // addend
+  result
+
+err = (input) ->
+  refute = (cond, msg) -> assert not cond, msg
+
+  -- figure out the appropriate error message
+  refute input\match('^What is *%?$'), 'syntax error'
+  assert input\match('^What is .+%?$'), 'unknown operation'
+  syntax_errs = re.compile [[
+    x <- s (op s op / num s num / op '?')
+    op <- 'plus' / 'minus' / 'multiplied by' / 'divided by'
+    num <- '-'? %d+
+    s <- %s+
+  ]]
+  refute re.find(input, syntax_errs), 'syntax error'
+  error 'unknown operation'
+
+{ :answer }

exercises/practice/wordy/.meta/spec_generator.moon

@@ -0,0 +1,16 @@
+{
+  module_name: 'Wordy',
+
+  generate_test: (case, level) ->
+    lines = if type(case.expected) == 'table'
+      {
+        "fn = -> Wordy.#{case.property} #{quote case.input.question}",
+        "assert.has.error fn, #{quote case.expected.error}"
+      }
+    else
+      {
+        "result = Wordy.#{case.property} #{quote case.input.question}",
+        "assert.are.equal #{case.expected}, result"
+      }
+    table.concat [indent line, level for line in *lines], '\n'
+}

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.moon

@@ -0,0 +1,4 @@
+{
+  answer: (question) ->
+    error 'Implement me'
+}

exercises/practice/wordy/wordy_spec.moon

@@ -0,0 +1,110 @@
+Wordy = require 'wordy'
+
+describe 'wordy', ->
+  it 'just a number', ->
+    result = Wordy.answer 'What is 5?'
+    assert.are.equal 5, result
+
+  pending 'just a zero', ->
+    result = Wordy.answer 'What is 0?'
+    assert.are.equal 0, result
+
+  pending 'just a negative number', ->
+    result = Wordy.answer 'What is -123?'
+    assert.are.equal -123, result
+
+  pending 'addition', ->
+    result = Wordy.answer 'What is 1 plus 1?'
+    assert.are.equal 2, result
+
+  pending 'addition with a left hand zero', ->
+    result = Wordy.answer 'What is 0 plus 2?'
+    assert.are.equal 2, result
+
+  pending 'addition with a right hand zero', ->
+    result = Wordy.answer 'What is 3 plus 0?'
+    assert.are.equal 3, result
+
+  pending 'more addition', ->
+    result = Wordy.answer 'What is 53 plus 2?'
+    assert.are.equal 55, result
+
+  pending 'addition with negative numbers', ->
+    result = Wordy.answer 'What is -1 plus -10?'
+    assert.are.equal -11, result
+
+  pending 'large addition', ->
+    result = Wordy.answer 'What is 123 plus 45678?'
+    assert.are.equal 45801, result
+
+  pending 'subtraction', ->
+    result = Wordy.answer 'What is 4 minus -12?'
+    assert.are.equal 16, result
+
+  pending 'multiplication', ->
+    result = Wordy.answer 'What is -3 multiplied by 25?'
+    assert.are.equal -75, result
+
+  pending 'division', ->
+    result = Wordy.answer 'What is 33 divided by -3?'
+    assert.are.equal -11, result
+
+  pending 'multiple additions', ->
+    result = Wordy.answer 'What is 1 plus 1 plus 1?'
+    assert.are.equal 3, result
+
+  pending 'addition and subtraction', ->
+    result = Wordy.answer 'What is 1 plus 5 minus -2?'
+    assert.are.equal 8, result
+
+  pending 'multiple subtraction', ->
+    result = Wordy.answer 'What is 20 minus 4 minus 13?'
+    assert.are.equal 3, result
+
+  pending 'subtraction then addition', ->
+    result = Wordy.answer 'What is 17 minus 6 plus 3?'
+    assert.are.equal 14, result
+
+  pending 'multiple multiplication', ->
+    result = Wordy.answer 'What is 2 multiplied by -2 multiplied by 3?'
+    assert.are.equal -12, result
+
+  pending 'addition and multiplication', ->
+    result = Wordy.answer 'What is -3 plus 7 multiplied by -2?'
+    assert.are.equal -8, result
+
+  pending 'multiple division', ->
+    result = Wordy.answer 'What is -12 divided by 2 divided by -3?'
+    assert.are.equal 2, result
+
+  pending 'unknown operation', ->
+    fn = -> Wordy.answer 'What is 52 cubed?'
+    assert.has.error fn, 'unknown operation'
+
+  pending 'Non math question', ->
+    fn = -> Wordy.answer 'Who is the President of the United States?'
+    assert.has.error fn, 'unknown operation'
+
+  pending 'reject problem missing an operand', ->
+    fn = -> Wordy.answer 'What is 1 plus?'
+    assert.has.error fn, 'syntax error'
+
+  pending 'reject problem with no operands or operators', ->
+    fn = -> Wordy.answer 'What is?'
+    assert.has.error fn, 'syntax error'
+
+  pending 'reject two operations in a row', ->
+    fn = -> Wordy.answer 'What is 1 plus plus 2?'
+    assert.has.error fn, 'syntax error'
+
+  pending 'reject two numbers in a row', ->
+    fn = -> Wordy.answer 'What is 1 plus 2 1?'
+    assert.has.error fn, 'syntax error'
+
+  pending 'reject postfix notation', ->
+    fn = -> Wordy.answer 'What is 1 2 plus?'
+    assert.has.error fn, 'syntax error'
+
+  pending 'reject prefix notation', ->
+    fn = -> Wordy.answer 'What is plus 1 2?'
+    assert.has.error fn, 'syntax error'