Functional Programming Spreadsheet

--- id: 64345b810a6e481e5e326849 title: Step 12 challengeType: 0 dashedName: step-12 --- # --description-- `range()` will return an array of numbers, which you need to convert back into characters. Chain the `.map()` method to your `range()` call. Pass a callback function that takes `code` as the parameter and implicitly returns the value of passing `code` to the `String.fromCharCode()` method. # --hints-- You should use the `.map()` method. ```js assert.lengthOf(code.match(/\.map\(/g), 2); ``` You should chain the `.map()` method to your `range` call. ```js assert.match(code, /const\s+charRange\s*=\s*\(\s*start\s*,\s*end\s*\)\s*=>\s*range\(\s*start\.charCodeAt\(\s*0\s*\)\s*,\s*end\.charCodeAt\(\s*0\s*\)\s*\)\.map\(/); ``` You should use arrow syntax for the `.map()` callback. ```js assert.match(code, /const\s+charRange\s*=\s*\(\s*start\s*,\s*end\s*\)\s*=>\s*range\(\s*start\.charCodeAt\(\s*0\s*\)\s*,\s*end\.charCodeAt\(\s*0\s*\)\s*\)\.map\(\s*(\(.*\)|[^\s()]+)\s*=>/); ``` Your `.map()` callback should take a `code` parameter. ```js assert.match(code, /const\s+charRange\s*=\s*\(\s*start\s*,\s*end\s*\)\s*=>\s*range\(\s*start\.charCodeAt\(\s*0\s*\)\s*,\s*end\.charCodeAt\(\s*0\s*\)\s*\)\.map\(\s*(\(\s*code\s*\)|code)\s*=>/); ``` Your `.map()` callback should use an implicit return. ```js assert.notMatch(code, /const\s+charRange\s*=\s*\(\s*start\s*,\s*end\s*\)\s*=>\s*range\(\s*start\.charCodeAt\(\s*0\s*\)\s*,\s*end\.charCodeAt\(\s*0\s*\)\s*\)\.map\(\s*(\(\s*code\s*\)|code)\s*=>\s*\{/); ``` Your `.map()` callback should return the result of calling `String.fromCharCode()`. ```js assert.match(code, /const\s+charRange\s*=\s*\(\s*start\s*,\s*end\s*\)\s*=>\s*range\(\s*start\.charCodeAt\(\s*0\s*\)\s*,\s*end\.charCodeAt\(\s*0\s*\)\s*\)\.map\(\s*(\(\s*code\s*\)|code)\s*=>\s*String\.fromCharCode\(/); ``` You should pass the variable `code` to `String.fromCharCode()`. ```js assert.match(code, /const\s+charRange\s*=\s*\(\s*start\s*,\s*end\s*\)\s*=>\s*range\(\s*start\.charCodeAt\(\s*0\s*\)\s*,\s*end\.charCodeAt\(\s*0\s*\)\s*\)\.map\(\s*(\(\s*code\s*\)|code)\s*=>\s*String\.fromCharCode\(\s*code\s*\)/); ``` # --seed-- ## --seed-contents-- ```html Functional Programming Spreadsheet

``` ```css #container { display: grid; grid-template-columns: 50px repeat(10, 200px); grid-template-rows: repeat(11, 30px); } .label { background-color: lightgray; text-align: center; vertical-align: middle; line-height: 30px; } ``` ```js const range = (start, end) => Array(end - start + 1).fill(start).map((element, index) => element + index); --fcc-editable-region-- const charRange = (start, end) => range(start.charCodeAt(0), end.charCodeAt(0)); --fcc-editable-region-- window.onload = () => { const container = document.getElementById("container"); const createLabel = (name) => { const label = document.createElement("div"); label.className = "label"; label.textContent = name; container.appendChild(label); } } ```