Q681. What are the built-in iterables?
Below are the list of built-in iterables in javascript, 1. Arrays and TypedArrays 2. Strings: Iterate over each character or Unicode code-points 3. Maps: iterate over its...
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Q682. What are the differences between for...of and for...in statements?
Both for...in and for...of statements iterate over js data structures. The only difference is over what they iterate: 1. for..in iterates over all enumerable property key...
Q683. How do you define instance and non-instance properties?
The Instance properties must be defined inside of class methods. For example, name and age properties defined inside constructor as below, ```javascript class Person { co...
Q684. What is the difference between isNaN and Number.isNaN?
1. **isNaN**: The global function `isNaN` converts the argument to a Number and returns true if the resulting value is NaN. 2. **Number.isNaN**: This method does not conv...
Q685. How to invoke an IIFE without any extra brackets?
Immediately Invoked Function Expressions(IIFE) requires a pair of parenthesis to wrap the function which contains set of statements. ```js (function (dt) { console.log(dt...
Q686. Is that possible to use expressions in switch cases?
You might have seen expressions used in switch condition but it is also possible to use for switch cases by assigning true value for the switch condition. Let's see the w...
Q687. What is the easiest way to ignore promise errors?
The easiest and safest way to ignore promise errors is void that error. This approach is ESLint friendly too. ```js await promise.catch((e) => void e); ```
Q688. How do style the console output using CSS?
You can add CSS styling to the console output using the CSS format content specifier %c. The console string message can be appended after the specifier and CSS style in a...
Q689. What is nullish coalescing operator (??)?
It is a logical operator that returns its right-hand side operand when its left-hand side operand is null or undefined, and otherwise returns its left-hand side operand. ...
Q690. How do you group and nest console output?
The `console.group()` can be used to group related log messages to be able to easily read the logs and use console.groupEnd()to close the group. Along with this, you can ...