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Get Started Free →Test understanding of recently written or accepted code
| Test case | Without → With | Effect | Δ tokens | Δ turns |
|---|---|---|---|---|
| case-01 | ✗→✓ | ▲ Improved | 15% | 0% |
| case-03 | ✗→✓ | ▲ Improved | 461% | 0% |
| case-05 | ✗→✓ | ▲ Improved | 11% | 0% |
| case-08 | ✗→✓ | ▲ Improved | 868% | 0% |
| case-09 | ✗→✓ | ▲ Improved | -30% | 0% |
Test understanding of recently written or accepted code.
/learn:quiz # Quiz on last code worked with
/learn:quiz error handling # Focus on specific aspect
/learn:quiz --hard # More challenging questionsWhen focus is specified (e.g., /learn:quiz error handling), prioritize questions about:
| Focus | Question Themes | |-------|-----------------| | error handling | Try/catch, error types, recovery strategies | | performance | Big-O, optimization, bottlenecks | | security | Input validation, XSS, injection | | testing | Test cases, edge cases, mocking | | architecture | Patterns, separation of concerns, SOLID | | types | TypeScript types, inference, generics |
--hardFor each question:
## Question 1 of 3
[Question text]
What's your answer?
---
(After user responds)
### Feedback
[Whether correct and why]
**Key insight**: [The concept this tests]
**Related concept**: [Something to explore further]
Ready for the next question?Summarize:
User: /learn:quiz
Claude: Looking at your last code - the useEffect hook for data fetching.
## Question 1 of 3
In your useEffect, you have an empty dependency array [].
What does this mean for when the effect runs?
User: It runs only once when the component mounts
Claude: ### Feedback
Correct! An empty dependency array means the effect runs only on mount
(and cleanup on unmount).
**Key insight**: The dependency array controls WHEN effects re-run.
**Related concept**: What happens with no array vs. [someValue]?
Ready for Question 2?$ARGUMENTS
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