Q861. What is the difference between dense and sparse arrays?
An array contains items at each index starting from first(0) to last(array.length - 1) is called as Dense array. Whereas if at least one item is missing at any index, the...
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Q862. What is a consumer?
A Consumer is a React component that subscribes to context changes. It requires a function as a child which receives current context value as argument and returns a react...
Q863. What are the different ways to create sparse arrays?
There are 4 different ways to create sparse arrays in JavaScript 1. **Array literal:** Omit a value when using the array literal ```js const justiceLeague = ["Superman", ...
Q864. How do you solve performance corner cases while using context?
The context uses reference identity to determine when to re-render, there are some gotchas that could trigger unintentional renders in consumers when a provider’s parent ...
Q865. What is the difference between setTimeout, setImmediate and process.nextTick?
1. **Set Timeout:** setTimeout() is to schedule execution of a one-time callback after delay milliseconds. 2. **Set Immediate:** The setImmediate function is used to exec...
Q866. What is the purpose of forward ref in HOCs?
Refs will not get passed through because ref is not a prop. It is handled differently by React just like **key**. If you add a ref to a HOC, the ref will refer to the out...
Q867. How do you reverse an array without modifying original array?
The `reverse()` method reverses the order of the elements in an array but it mutates the original array. Let's take a simple example to demonistrate this case, ```javascr...
Q868. Is ref argument available for all functions or class components?
Regular function or class components don’t receive the ref argument, and ref is not available in props either. The second ref argument only exists when you define a compo...
Q869. How do you create custom HTML element?
The creation of custom HTML elements involves two main steps, 1. **Define your custom HTML element:** First you need to define some custom class by extending HTMLElement ...
Q870. Why do you need additional care for component libraries while using forward refs?
When you start using forwardRef in a component library, you should treat it as a breaking change and release a new major version of your library. This is because your lib...