Validate one step and explain its errors
See this course’s project requirements
A local two-step fictional workshop-registration form with labeled fields, preserved back navigation, error summary and a review-before-submit screen; no data is sent.
Keep your working files in your own notebook or software. Save a private description, checklist, and work link in My Proof.
What to include
- Create a step map and verify that Next, Review, and local completion have distinct behavior.
- Produce an inspected label/group map with working for/id associations.
- Record missing, malformed, endpoint, and repaired input behavior with actionable error messages.
- Build a Back-navigation matrix proving that edits change the intended value and preserve other fields.
- Produce a literal-text review that rejects an invalid complete request and reflects changed valid values.
- Deliver source plus separate rule-test and rendered-journey evidence, with honest unverified checks.
Review and revise
Use these criteria to check your work and choose what to improve.
- The implementation or declared simulation follows the supplied contract and retains inspectable original inputs.
- Normal, boundary and rejected cases are recorded with expected versus observed results.
- The changed case has a correct explanation and does not rely on hidden state.
- The project includes source, outputs, instructions and honest tool, privacy and verification limits.
Want more background?
The idea in everyday life
Empty nickname is invalid; sessions are am or pm; seats are whole numbers 1–4.
Validation checks a stated rule; feedback names the affected field and tells the learner how to repair the value. Hidden later fields should not block the current step.
Validate one step and explain its errors — original worked practice
Validation checks a stated rule; feedback names the affected field and tells the learner how to repair the value. Hidden later fields should not block the current step.
Empty nickname is invalid; sessions are am or pm; seats are whole numbers 1–4.
1. Step 1
Submit step 1 with empty values. Read the error summary and activate its nickname link.
You should see: Focus moves to the empty nickname field.
Validation checks a stated rule; feedback names the affected field and tells the learner how to repair the value. Hidden later fields should not block the current step.
2. Step 2
Enter Nova and choose Morning; continue. Enter 2.5 in seats and activate Next.
You should see: An error requests a whole number from 1 to 4; review stays hidden.
Validation checks a stated rule; feedback names the affected field and tells the learner how to repair the value. Hidden later fields should not block the current step.
3. Step 3
Inspect errors(d, step): step 0 checks only nickname/session; step 1 checks seats. Replace 2.5 with 2.
You should see: The repaired value permits review.
Validation checks a stated rule; feedback names the affected field and tells the learner how to repair the value. Hidden later fields should not block the current step.
4. Step 4
Run node test-form.mjs; retain the empty-field and decimal-seat checks beside the visible test observations.
You should see: An error/repair record that separates logic tests from browser focus observations.
Validation checks a stated rule; feedback names the affected field and tells the learner how to repair the value. Hidden later fields should not block the current step.
What to finish
Record missing, malformed, endpoint, and repaired input behavior with actionable error messages.
Watch for this
Moving focus to a hidden later field or returning only a vague failure message.
How can I tell I understand it?
Demonstrate the rule: Validation checks a stated rule; feedback names the affected field and tells the learner how to repair the value. Hidden later fields should not block the current step. Use the supplied variant to distinguish a changed result from a broken implementation.
Quick knowledge check
Answer all 3 questions. Get at least 2 right and the lesson completes automatically.
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Answer all 3 questions above and get at least 2 right. You can review the explanations and try again.
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Source & access notes · checked 2026-10-01
Relevant documented module/API behavior inspected during expansion authoring; actual execution evidence is recorded separately. No grant eligibility is established.
Access: Official page retrieved with the web reader on 2026-10-01. Documentation reading does not certify execution in every native tool or browser.
Reuse: Original local practice files, fictional data, worked examples and questions. Concepts paraphrased and linked; source exercises are not copied.
Source & access notes · checked 2026-10-01
Relevant documented module/API behavior inspected during expansion authoring; actual execution evidence is recorded separately. No grant eligibility is established.
Access: Official page retrieved with the web reader on 2026-10-01. Documentation reading does not certify execution in every native tool or browser.
Reuse: Original local practice files, fictional data, worked examples and questions. Concepts paraphrased and linked; source exercises are not copied.
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