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Rule priority, scope & exceptions
Use this to align rules with the senior-level structure (P0/P1/P2, scope, exceptions/tradeoffs).
frontend ruleP0universalStack: TypeScript
typescriptoptional-chainingnull-safety
Guard the container before indexing an optionally-chained value
Optional chaining stops at the first nullish link; indexing the result of a possibly-undefined access still throws.
PR: hegnar-ws · org-mining-hist-2026-06Created: Jun 18, 2026
Bad example
Old codetypescript
| 1 | if (!data?.items[0]?.value) { return; } |
Explanation (EN)
Objašnjenje (HR)
Good example
New codetypescript
| 1 | if (!data || !data.items || !data.items[0]?.value) { return; } |
Explanation (EN)
Objašnjenje (HR)