Q1021. What is heap?
Heap(Or memory heap) is the memory location where objects are stored when we define variables. i.e, This is the place where all the memory allocations and de-allocation t...
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Q1022. How to avoid using relative path imports in create-react-app?
Create a file called `.env` in the project root and write the import path: ``` NODE_PATH=src/app ``` After that restart the development server. Now you should be able to ...
Q1023. What is an event table?
Event Table is a data structure that stores and keeps track of all the events which will be executed asynchronously like after some time interval or after the resolution ...
Q1024. How to update a component every second?
You need to use `setInterval()` to trigger the change, but you also need to clear the timer when the component unmounts to prevent errors and memory leaks. ```javascript ...
Q1025. Why is a component constructor called only once?
React's _reconciliation_ algorithm assumes that without any information to the contrary, if a custom component appears in the same place on subsequent renders, it's the s...
Q1026. What is the difference between shim and polyfill?
A shim is a library that brings a new API to an older environment, using only the means of that environment. It isn't necessarily restricted to a web application. For exa...
Q1027. How to define constants in React?
You can use ES7 `static` field to define constant. ```javascript class MyComponent extends React.Component { static DEFAULT_PAGINATION = 10; } ```
Q1028. How do you detect primitive or non primitive value type?
In JavaScript, primitive types include boolean, string, number, BigInt, null, Symbol and undefined. Whereas non-primitive types include the Objects. But you can easily id...
Q1029. How to programmatically trigger click event in React?
You could use the ref prop to acquire a reference to the underlying `HTMLInputElement` object through a callback, store the reference as a class property, then use that r...
Q1030. What is babel?
Babel is a JavaScript transpiler to convert ECMAScript 2015+ code into a backwards compatible version of JavaScript in current and older browsers or environments. Some of...