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Rule priority, scope & exceptions

Use this to align rules with the senior-level structure (P0/P1/P2, scope, exceptions/tradeoffs).

PriorityP2 — style, consistency, readabilityScopeUniversal — language-agnostic, broadly applicable

Exceptions / tradeoffs (EN)Iznimke / tradeoffi (HR)

frontend ruleP2universalStack: javascript

singletonglobalsnullish-coalescingreadability

Lazily initialize a shared global with nullish assignment

Create-or-reuse a shared global instance (like an IntersectionObserver) with ??= so multiple callers share one instance, expressed in a single readable line.

PR: hegnar-web · org-mining-hist-2026-06Created: Jun 19, 2026

Bad example

Old codejavascript

1	`if (!window.parallaxObserver) {`
2	`window.parallaxObserver = new IntersectionObserver(cb);`
3	`}`
4	`window.parallaxObserver.observe(el);`

Explanation (EN)

Objašnjenje (HR)

Good example

New codejavascript

1	`window.parallaxObserver ??= new IntersectionObserver(cb);`
2	`window.parallaxObserver.observe(el);`

Explanation (EN)

Objašnjenje (HR)

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