Files
Naomi Carrigan fe71a9cf25 feat: new js cert (#45873)
* chore: move files

* wip: i have no idea what i am doing

* feat: finish up the logic

* chore: use order from randy sheet

* chore: standardise titles

* feat: fix layout for new js projects

* fix: utils test

* fix: challenge tests

* fix: ignore show new curriculum on non-english tests

* chore: help category????

* fix: if these tests would fail locally that'd be great

* chore: duplicate ids
2022-05-16 11:53:45 +02:00

6.6 KiB

id, title, challengeType, dashedName
id title challengeType dashedName
5d792537b6cadae0f4b0cda1 Step 94 0 step-94

--description--

The slice method takes two arguments. It extracts characters from the string from the index specified by the first argument up to (but not including) the second argument. The index starts at 0.

Use the slice method to log the first two letters of value to the console.

--hints--

See description above for instructions.

assert(code.replace(/\s/g, '').includes('console.log(value.slice(0,2))'));

--seed--

--before-user-code--

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Spreadsheet</title>
  <style>
    #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;
    }
  </style>
</head>
<body>
<div id="container">
  <div></div>
</div>

--after-user-code--

</body>
</html>

--seed-contents--

<script>

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, (_, arg1, fn, arg2) =>
    infixToFunction[fn](parseFloat(arg1), parseFloat(arg2))
  );

const highPrecedence = str => {
  const regex = /([0-9.]+)([*\/])([0-9.]+)/;
  const str2 = infixEval(str, regex);
  return str === str2 ? str : highPrecedence(str2);
};

const spreadsheetFunctions = {
  "": x => x
};

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

const range = (start, end) =>
  start > end ? [] : [start].concat(range(start + 1, end));

const charRange = (start, end) =>
  range(start.charCodeAt(0), end.charCodeAt(0)).map(x =>
    String.fromCharCode(x)
  );

const evalFormula = x => {
  const rangeRegex = /([A-J])([1-9][0-9]?):([A-J])([1-9][0-9]?)/gi;
  const rangeFromString = (n1, n2) => range(parseInt(n1), parseInt(n2));
  const elemValue = n => c => document.getElementById(c + n).value;
  const addChars = c1 => c2 => n => charRange(c1, c2).map(elemValue(n));
  const varRangeExpanded = x.replace(rangeRegex, (_, c1, n1, c2, n2) =>
    rangeFromString(n1, n2).map(addChars(c1)(c2))
  );
  const varRegex = /[A-J][1-9][0-9]?/gi;
  const varExpanded = varRangeExpanded.replace(
    varRegex,
    match => document.getElementById(match.toUpperCase()).value
  );
  const functionExpanded = applyFn(varExpanded);
  return functionExpanded === x
    ? functionExpanded
    : evalFormula(functionExpanded);
};

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(x => {
    createLabel(x);
    letters.forEach(y => {
      const input = document.createElement("input");
      input.type = "text";
      input.id = y + x;
      input.onchange = update;
      container.appendChild(input);
    });
  });
};

const update = event => {
  const element = event.target;
  const value = element.value.replace(/\s/g, "");
  if (!value.includes(element.id) && value[0] === "=") {}
};


</script>

--solutions--

<script>
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, (_, arg1, fn, arg2) =>
    infixToFunction[fn](parseFloat(arg1), parseFloat(arg2))
  );

const highPrecedence = str => {
  const regex = /([0-9.]+)([*\/])([0-9.]+)/;
  const str2 = infixEval(str, regex);
  return str === str2 ? str : highPrecedence(str2);
};

const spreadsheetFunctions = {
  "": x => x
};

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

const range = (start, end) =>
  start > end ? [] : [start].concat(range(start + 1, end));

const charRange = (start, end) =>
  range(start.charCodeAt(0), end.charCodeAt(0)).map(x =>
    String.fromCharCode(x)
  );

const evalFormula = x => {
  const rangeRegex = /([A-J])([1-9][0-9]?):([A-J])([1-9][0-9]?)/gi;
  const rangeFromString = (n1, n2) => range(parseInt(n1), parseInt(n2));
  const elemValue = n => c => document.getElementById(c + n).value;
  const addChars = c1 => c2 => n => charRange(c1, c2).map(elemValue(n));
  const varRangeExpanded = x.replace(rangeRegex, (_, c1, n1, c2, n2) =>
    rangeFromString(n1, n2).map(addChars(c1)(c2))
  );
  const varRegex = /[A-J][1-9][0-9]?/gi;
  const varExpanded = varRangeExpanded.replace(
    varRegex,
    match => document.getElementById(match.toUpperCase()).value
  );
  const functionExpanded = applyFn(varExpanded);
  return functionExpanded === x
    ? functionExpanded
    : evalFormula(functionExpanded);
};

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(x => {
    createLabel(x);
    letters.forEach(y => {
      const input = document.createElement("input");
      input.type = "text";
      input.id = y + x;
      input.onchange = update;
      container.appendChild(input);
    });
  });
};

const update = event => {
  const element = event.target;
  const value = element.value.replace(/\s/g, "");
  if (!value.includes(element.id) && value[0] === "=") {
    console.log(value.slice(0, 2));
  }
};
</script>