react-useref-duplicate-prevention-race

name	react-useref-duplicate-prevention-race
description	Fix React duplicate detection race conditions using useRef for synchronous checks. Use when: (1) Rapid successive function calls bypass duplicate/spam detection despite state-based checking logic, (2) Rate limiting or cooldown logic fails when triggered multiple times quickly, (3) Duplicate items appear in lists despite deduplication code, (4) State-based guards don't prevent re-entry in event handlers. Solves race condition where multiple calls read the same stale state value before any setState completes. Covers React hooks patterns with useRef, useState, useCallback for duplicate prevention, spam protection, rate limiting, and synchronous guard checks.
author	Claude Code
version	1.0.0
date	2026-02-02T00:00:00.000Z

React useRef for Duplicate Prevention Race Conditions

Problem

When implementing duplicate detection, spam prevention, or rate limiting in React using state, rapid successive function calls can bypass the checks due to React's asynchronous state updates. All calls read the same stale state value before any setState completes, allowing duplicates through.

Common Scenario: Alert/notification system where rapid form validation errors trigger multiple identical alerts despite duplicate detection logic.

Context / Trigger Conditions