js-set-map-lookups

What problem does it solve?

This Skill replaces repeated O(n) membership tests performed with array.includes() by using native Set/Map lookups, delivering faster performance in data processing tasks.

Core Features & Use Cases

• Use Set.has and Map.has for constant-time membership checks.
• Seamlessly convert array-based lookups to Set/Map lookups in existing code.
• Use Case: efficiently filter large collections by an allowed-id set or validate items against a permitted set.

Quick Start

Replace a typical array.includes membership test with Set.has by initializing a Set with the allowed identifiers and using has() in the lookup, e.g., new Set(['a','b',...]) and items.filter(item => allowed.has(item.id)).