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Rule priority, scope & exceptions
Use this to align rules with the senior-level structure (P0/P1/P2, scope, exceptions/tradeoffs).
fullstack ruleP1universalStack: javascript
defensive-programmingerror-handlingcorrectness
Guard against missing or empty data before using it
Handle the cases where fetched data is absent or empty so the UI degrades gracefully instead of throwing.
PR: hegnar-web · org-mining-hist-2026-06Created: Jun 19, 2026
Bad example
Old codejavascript
| 1 | const decoded = jwt.decode(state); |
| 2 | render(decoded.plan.paymentMethods); |
Explanation (EN)
Objašnjenje (HR)
Good example
New codejavascript
| 1 | const decoded = jwt.decode(state); |
| 2 | if (!decoded?.plan?.paymentMethods?.length) { |
| 3 | return renderFallback(); |
| 4 | } |
| 5 | render(decoded.plan.paymentMethods); |
Explanation (EN)
Objašnjenje (HR)