add isogram (#29)

* exercise boilerplate

* example solution

Author: TheRealOwenRees

config.json

@@ -77,6 +77,14 @@
         "prerequisites": [],
         "difficulty": 2
       },
+      {
+        "slug": "isogram",
+        "name": "Isogram",
+        "uuid": "7cf8a5d3-2b4e-4f9d-bd01-9badc2dc82e5",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 2
+      },
       {
         "slug": "leap",
         "name": "Leap",

exercises/practice/isogram/.docs/instructions.md

@@ -0,0 +1,14 @@
+# Instructions
+
+Determine if a word or phrase is an isogram.
+
+An isogram (also known as a "non-pattern word") is a word or phrase without a repeating letter, however spaces and hyphens are allowed to appear multiple times.
+
+Examples of isograms:
+
+- lumberjacks
+- background
+- downstream
+- six-year-old
+
+The word _isograms_, however, is not an isogram, because the s repeats.

exercises/practice/isogram/.gitignore

@@ -0,0 +1,2 @@
+node_modules
+**/*.res.js

exercises/practice/isogram/.meta/Isogram.res

@@ -0,0 +1,17 @@
+let isIsogram = phrase => {
+  let charSet = Set.make()
+
+  phrase
+  ->String.toLowerCase
+  ->String.split("")
+  ->Array.every(c => {
+    if c == " " || c == "-" {
+      true
+    } else if charSet->Set.has(c) {
+      false
+    } else {
+      charSet->Set.add(c)
+      true
+    }
+  })
+}

exercises/practice/isogram/.meta/Isogram.resi

@@ -0,0 +1 @@
+let isIsogram: string => bool

exercises/practice/isogram/.meta/config.json

@@ -0,0 +1,21 @@
+{
+  "authors": [
+    "therealowenrees"
+  ],
+  "files": {
+    "solution": [
+      "src/Isogram.res",
+      "src/Isogram.resi"
+    ],
+    "test": [
+      "tests/Isogram_test.res"
+    ],
+    "example": [
+      ".meta/Isogram.res",
+      ".meta/Isogram.resi"
+    ]
+  },
+  "blurb": "Determine if a word or phrase is an isogram.",
+  "source": "Wikipedia",
+  "source_url": "https://en.wikipedia.org/wiki/Isogram"
+}

exercises/practice/isogram/.meta/testTemplate.js

@@ -0,0 +1,17 @@
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+import { assertEqual } from "../../../../test_generator/assertions.js";
+import { generateTests } from '../../../../test_generator/testGenerator.js';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+const slug = path.basename(path.resolve(__dirname, '..'))
+
+// EDIT THIS WITH YOUR ASSERTIONS
+export const assertionFunctions = [ assertEqual ]
+
+// EDIT THIS WITH YOUR TEST TEMPLATES
+export const template = (c) => {
+  return `assertEqual(~message="${c.description}", isIsogram("${c.input.phrase}"), ${c.expected})`
+}
+
+generateTests(__dirname, slug, assertionFunctions, template)

exercises/practice/isogram/.meta/tests.toml

@@ -0,0 +1,52 @@
+# 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.
+
+[a0e97d2d-669e-47c7-8134-518a1e2c4555]
+description = "empty string"
+
+[9a001b50-f194-4143-bc29-2af5ec1ef652]
+description = "isogram with only lower case characters"
+
+[8ddb0ca3-276e-4f8b-89da-d95d5bae78a4]
+description = "word with one duplicated character"
+
+[6450b333-cbc2-4b24-a723-0b459b34fe18]
+description = "word with one duplicated character from the end of the alphabet"
+
+[a15ff557-dd04-4764-99e7-02cc1a385863]
+description = "longest reported english isogram"
+
+[f1a7f6c7-a42f-4915-91d7-35b2ea11c92e]
+description = "word with duplicated character in mixed case"
+
+[14a4f3c1-3b47-4695-b645-53d328298942]
+description = "word with duplicated character in mixed case, lowercase first"
+
+[423b850c-7090-4a8a-b057-97f1cadd7c42]
+description = "hypothetical isogrammic word with hyphen"
+
+[93dbeaa0-3c5a-45c2-8b25-428b8eacd4f2]
+description = "hypothetical word with duplicated character following hyphen"
+
+[36b30e5c-173f-49c6-a515-93a3e825553f]
+description = "isogram with duplicated hyphen"
+
+[cdabafa0-c9f4-4c1f-b142-689c6ee17d93]
+description = "made-up name that is an isogram"
+
+[5fc61048-d74e-48fd-bc34-abfc21552d4d]
+description = "duplicated character in the middle"
+
+[310ac53d-8932-47bc-bbb4-b2b94f25a83e]
+description = "same first and last characters"
+
+[0d0b8644-0a1e-4a31-a432-2b3ee270d847]
+description = "word with duplicated character and with two hyphens"

exercises/practice/isogram/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 Exercism
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.