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Nhan Nguyen
Nhan Nguyen

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JavaScript Design Patterns - Creational - Prototype

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Prototype pattern creates new objects based on an existing one with default property values.

In the example below, we can use the clone() method to create a new object Fruit with the same name and weight as its parent.

class Fruit {
  constructor(name, weight) { = name;
    this.weight = weight;

  clone() {
    return new Fruit(, this.weight);

export default Fruit;
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šŸ‘‰ Use this pattern when:

āž– Our code should not depend on the concrete classes of objects that you need to copy.

āž– We want to reduce the number of subclasses that only differ in how they initialize their respective objects.

šŸš€ Pros:

āž– We can clone objects without coupling to their concrete classes.

āž– We can eliminate repeated initialization code in favor of cloning pre-built prototypes.

āž– We can produce complex objects more conveniently.

āž– We get an alternative to inheritance when dealing with configuration presets for complex objects.

ā›” Cons:

āž– Cloning complex objects that have circular references might be very tricky.

I hope you found it useful. Thanks for reading. šŸ™

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