debug:react
React Debugging Guide
A systematic approach to debugging React applications, covering common error patterns, modern debugging tools, and step-by-step resolution strategies.
Common Error Patterns
1. "Cannot read property of undefined" / "TypeError: X is undefined"
Cause: Accessing properties on null/undefined values, often from:
- Uninitialized state
- API data not yet loaded
- Incorrect prop drilling
Solutions:
// Problem: Accessing nested property before data loads
const name = user.profile.name; // Error if user is undefined
// Solution 1: Optional chaining
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