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How do you set the prototype of one object to another?

Peer-reviewed by HireXTech Technical Panel Updated for 2025/2026 hiring Editorial standards
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01
Core Competency

Assesses fundamental understanding of JavaScript conventions, runtime behavior, and memory/performance considerations.

02
Evaluation Criteria

Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.

Comprehensive Model Answer Verified Solution

You can use the Object.setPrototypeOf() method that sets the prototype (i.e., the internal Prototype property) of a specified object to another object or null. For example, if you want to set prototype of a square object to rectangle object would be as follows,

      Object.setPrototypeOf(Square.prototype, Rectangle.prototype);
      Object.setPrototypeOf({}, null);
      

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