Q511. What is an object initializer?
An object initializer is an expression that describes the initialization of an Object. The syntax for this expression is represented as a comma-delimited list of zero or ...
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Q512. How do you use immer library for state updates?
Immer library enforces the immutability of state based on **copy-on-write** mechanism. It uses JavaScript proxy to keep track of updates to immutable states. Immer has 3 ...
Q513. What is a constructor method?
The constructor method is a special method for creating and initializing an object created within a class. If you do not specify a constructor method, a default construct...
Q514. What are the benefits of preventing the direct state mutations?
In React and modern JavaScript state management, **immutability** (preventing direct mutation of state objects and arrays) is a core foundational architectural requiremen...
Q515. What happens if you write constructor more than once in a class?
The "constructor" in a class is a special method and it should be defined only once in a class. i.e, If you write a constructor method more than once in a class it will t...
Q516. What are the preferred and non-preferred array operations for updating the state?
The below table represent preferred and non-preferred array operations for updating the component state. | Action | Preferred | Non-preferred | | --------- | ------------...
Q517. How do you call the constructor of a parent class?
You can use the `super` keyword to call the constructor of a parent class. Remember that `super()` must be called before using `this` reference. Otherwise it will cause a...
Q518. What will happen by defining nested function components?
Technically it is possible to write nested function components but it is not suggested to write nested function definitions. Because it leads to unexpected bugs and perfo...
Q519. How do you get the prototype of an object?
You can use the `Object.getPrototypeOf(obj)` method to return the prototype of the specified object. i.e. The value of the internal `prototype` property. If there are no ...
Q520. Can I use keys for non-list items?
Keys are primarily used for rendering list items but they are not just for list items. You can also use them React to distinguish components. By default, React uses order...