Pattern: Array#includes() for repeated lookups
Issue: -
When performing frequent existence checks, using Set#has() is more performant than Array#includes(). If an array is primarily used for lookup operations, consider converting it to a Set.
Example of incorrect code:
const array = [1, 2, 3];
const hasValue = (value) => array.includes(value);Example of correct code:
const set = new Set([1, 2, 3]);
const hasValue = (value) => set.has(value);
// Single lookup is fine with array
const array = [1, 2, 3];
const hasOne = array.includes(1);