Implement classNames Utility

easyJS SpecificJS / TS3 tests

Problem Statement

Implement a `classNames(...args)` helper (similar to clsx or classnames) that conditionally joins CSS class names together. Handles strings, numbers, arrays, and objects with truthy/falsy values.

Examples

Example 1:
classNames('btn', { 'btn-primary': true, 'btn-disabled': false }); // 'btn btn-primary'

Example 2:
classNames('a', ['b', { c: true, d: false }], null, undefined, 0); // 'a b c'

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Implement classNames Utility

Problem Statement

Examples

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