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Delegated Event Handler (E)

By FrontendAtlas Team · Updated Jan 31, 2026

Implement delegate(root, eventType, selector, handler) for event delegation. Requirements: 1) Attach one event listener to root. 2) When an event fires, if event.target (or one of its ancestors up to root) matches selector, call handler(event, matchedElement). 3) Return a cleanup function that removes the listener.…

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Delegated Event Handler (E): Implement delegate(root, eventType, selector, handler) for event delegation. Requirements: 1) Attach one event listener to root. 2) When an event fires, if event.target (or…. Expect dom and events decisions under intermediate level constraints.

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