JavaScript Foundations·Practice drills 7

Drill 10: Invalid input — Errors and debugging

Describe what happens when the input is invalid.

Beginner 5 min read Lesson 173 of 480 Challenge included
What you will be able to do
  • Describe what happens when the input is invalid.

Practice task

Describe what happens when the input is invalid.

validate.jsJavaScript
function parseScore(raw) {
  const score = Number(raw);

  if (!Number.isFinite(score)) {
    throw new TypeError(`Invalid score: ${raw}`);
  }

  if (score < 0 || score > 100) {
    throw new RangeError("Score must be between 0 and 100");
  }

  return score;
}
Your turn

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Describe what happens when the input is invalid.

TEXT · starter
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Lesson 173 of 480 · 0% of course