JavaScript · question
Question 3 of 130
Explain the concept of "use strict" in JavaScript
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"use strict" enables strict mode, which catches common coding mistakes and prevents certain actions. It makes JavaScript more secure and optimized by:
- Preventing use of undeclared variables
- Disallowing duplicate parameter names
- Making
this undefined in functions (not global object)
- Preventing deletion of variables, functions, or arguments
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