Learn Functional Programming by Building a Spreadsheet - Step 91

JavaScript
1

Tell us what’s happening:

Please help me. I have tried so many time but I couldn’t.

Your code so far

<!-- file: index.html -->
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1" />
    <link rel="stylesheet" href="./styles.css" />
    <title>Functional Programming Spreadsheet</title>
  </head>
  <body>
    <div id="container">
      <div></div>
    </div>
    <script src="./script.js"></script>
  </body>
</html>

/* file: styles.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;
}

/* file: script.js */
const infixToFunction = {
  "+": (x, y) => x + y,
  "-": (x, y) => x - y,
  "*": (x, y) => x * y,
  "/": (x, y) => x / y,
}

const infixEval = (str, regex) => str.replace(regex, (_match, arg1, operator, arg2) => infixToFunction[operator](parseFloat(arg1), parseFloat(arg2)));

const highPrecedence = str => {
  const regex = /([\d.]+)([*\/])([\d.]+)/;
  const str2 = infixEval(str, regex);
  return str === str2 ? str : highPrecedence(str2);
}

const isEven = num => num % 2 === 0;
const sum = nums => nums.reduce((acc, el) => acc + el, 0);
const average = nums => sum(nums) / nums.length;

const median = nums => {
  const sorted = nums.slice().sort((a, b) => a - b);
  const length = sorted.length;
  const middle = length / 2 - 1;
  return isEven(length)
    ? average([sorted[middle], sorted[middle + 1]])
    : sorted[Math.ceil(middle)];
}

const spreadsheetFunctions = {
  sum,
  average,
  median
}

const applyFunction = str => {
  const noHigh = highPrecedence(str);
  const infix = /([\d.]+)([+-])([\d.]+)/;
  const str2 = infixEval(noHigh, infix);
  const functionCall = /([a-z0-9]*)\(([0-9., ]*)\)(?!.*\()/i;
  const toNumberList = args => args.split(",").map(parseFloat);
  const apply = (fn, args) => spreadsheetFunctions[fn.toLowerCase()](toNumberList(args));
  return str2.replace(functionCall, (match, fn, args) => spreadsheetFunctions.hasOwnProperty(fn.toLowerCase()) ? apply(fn, args) : match);
}

const range = (start, end) => Array(end - start + 1).fill(start).map((element, index) => element + index);
const charRange = (start, end) => range(start.charCodeAt(0), end.charCodeAt(0)).map(code => String.fromCharCode(code));

const evalFormula = (x, cells) => {
  const idToText = id => cells.find(cell => cell.id === id).value;
  const rangeRegex = /([A-J])([1-9][0-9]?):([A-J])([1-9][0-9]?)/gi;
  const rangeFromString = (num1, num2) => range(parseInt(num1), parseInt(num2));
  const elemValue = num => character => idToText(character + num);
  const addCharacters = character1 => character2 => num => charRange(character1, character2).map(elemValue(num));
  const rangeExpanded = x.replace(rangeRegex, (_match, char1, num1, char2, num2) => rangeFromString(num1, num2).map(addCharacters(char1)(char2)));
  const cellRegex = /[A-J][1-9][0-9]?/gi;
  const cellExpanded = rangeExpanded.replace(cellRegex, match => idToText(match.toUpperCase()));
  const functionExpanded = applyFunction(cellExpanded);
  return functionExpanded === x ? functionExpanded : evalFormula(functionExpanded, cells);
}

window.onload = () => {
  const container = document.getElementById("container");
  const createLabel = (name) => {
    const label = document.createElement("div");
    label.className = "label";
    label.textContent = name;
    container.appendChild(label);
  }
  const letters = charRange("A", "J");
  letters.forEach(createLabel);
  range(1, 99).forEach(number => {
    createLabel(number);
    letters.forEach(letter => {
      const input = document.createElement("input");
      input.type = "text";
      input.id = letter + number;
      input.ariaLabel = letter + number;
      input.onchange = update;
      container.appendChild(input);
    })
  })
}


// User Editable Region

const update = event => {
  const element = event.target;
  const value = element.value.replace(/\s/g, "");
  if (!value.includes(element.id).evalFormula && value.startsWith('=')) {
element.value = evalFormula();
  }
}

// User Editable Region

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36

Challenge Information:

Learn Functional Programming by Building a Spreadsheet - Step 91

2

Inside your if statement, set the value of the element to be the result of your evalFormula() function. Do not pass any arguments yet.

If your code doesn’t work, try resetting the code and writing it again

3

Not working by resetting the code

4

avoid changing things you are not asked to change and it will pass

5

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