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Rule priority, scope & exceptions
Use this to align rules with the senior-level structure (P0/P1/P2, scope, exceptions/tradeoffs).
mobile ruleP0stack specificStack: kotlin
kotlinnull-safetycrash
Avoid the !! not-null assertion in Kotlin
!! throws NPE when the value is null; use safe calls (?.), the Elvis operator (?:), or restructure so nullability is handled.
PR: mobile-canon-2026-06Created: Jul 5, 2026
Bad example
Old codekotlin
| 1 | val name = user!!.name |
Explanation (EN)
Objašnjenje (HR)
Good example
New codekotlin
| 1 | val name = user?.name ?: return |
Explanation (EN)
Objašnjenje (HR)