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Undeclared Variables in Strict Mode

Undeclared Variables in Strict Mode

In strict mode, assigning to an undeclared variable throws a ReferenceError. Without strict mode, it silently creates a global variable.

Challenge: Write testUndeclared() that:

  1. Uses eval to run code in strict mode that assigns to an undeclared variable
  2. Wraps it in try/catch
  3. Returns true if a ReferenceError is caught, false otherwise
💡 Hints (2)
  • • Use eval() to run code in strict mode
  • • Wrap the eval in try/catch to catch the ReferenceError