Common use cases of 'shallow copies'

Shallow copies are useful in scenarios where you need to create a new object with the same top-level properties as the original, but you don't need to deeply clone nested objects. Here are some common use cases:

1. **State Management in React**: When updating the state in React, you often create a shallow copy of the state object to ensure immutability. This allows React to detect changes and re-render components efficiently.

   ```javascript

   const newState = { ...oldState, newProperty: value };

   ```

2. **Merging Objects**: When you want to merge two or more objects, a shallow copy can be used to combine their properties.

   ```javascript

   const mergedObject = { ...object1, ...object2 };

   ```

3. **Cloning Simple Objects**: If you have an object with only primitive values (numbers, strings, booleans), a shallow copy is sufficient to create a new independent object.

   ```javascript

   const original = { a: 1, b: 2 };

   const copy = { ...original };

   ```

4. **Performance Considerations**: Shallow copies are faster and use less memory compared to deep copies, making them suitable for performance-critical applications where deep cloning is unnecessary.

In summary, shallow copies are ideal when you need a quick and efficient way to duplicate an object without deeply cloning nested structures.