The method _________ is used to execute code after a Promise is either fulfilled or rejected.

finally()
done()
complete()
finalize()

The correct method is finally(). The finally() method is used to specify a function that will be executed regardless of whether the Promise is fulfilled or rejected. It allows you to perform cleanup or finalization tasks.

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Tree shaking is most effective when modules use _______ exports rather than wildcard exports.

Named
Default
All
Individual

Tree shaking is a technique in JavaScript used to eliminate unused code during the build process. When modules use named exports, it allows the bundler to selectively include only the functions or variables that are actually used, making tree shaking more effective. Default exports and wildcard exports can complicate this process, leading to less efficient tree shaking.

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If an arrow function is written with a single expression, the return value is the result of the expression without using the ________ keyword.

Break
Return
Yield
Exit

In arrow functions, if the function body consists of a single expression, you can omit the curly braces {} and the return keyword. The return value will be the result of the expression automatically.

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To access a parent class's method in a child class, the __________ keyword is used inside the method.

super
this
parent
extends

In JavaScript, the super keyword is used to refer to the parent class. When used inside a method in a child class, it allows you to call the corresponding method in the parent class. This is particularly useful for accessing and invoking the parent class's method from within the child class.

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In terms of scope, how do variables and functions behave differently in ES6 Modules compared to CommonJS modules?

Variables and functions have block scope
Variables have block scope, functions have global scope
Variables and functions have global scope
Variables have global scope, functions have block scope

ES6 Modules introduce block scope for both variables and functions, offering better encapsulation. In contrast, CommonJS has function-level scope for variables and global scope for functions, leading to potential issues with variable leakage.

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If a module exports several named items, how can you import all of them at once?

import * as allExports from 'module';
import { export1, export2 } from 'module';
import allExports from 'module';
import { * } from 'module';

To import all named exports from a module at once, you use the syntax import * as allExports from 'module';. This creates an object containing all the exports, and you can access them using dot notation, e.g., allExports.exportName.

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What is a key difference between a Map and a WeakMap in JavaScript?

Both can store key-value pairs, but the keys in WeakMap must be objects, and they don't prevent the objects from being garbage collected.
Maps allow any data type as keys, while WeakMaps only allow objects as keys.
Maps are iterable, while WeakMaps are not iterable.
WeakMaps have a getKeys method to retrieve all keys.

Maps are versatile and allow various data types as keys, while WeakMaps are designed for enhanced privacy, with keys limited to objects and no direct method for key retrieval.

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In a node.js application, how would you handle errors when performing multiple asynchronous operations in parallel?

Implementing a try-catch block around each asynchronous operation
Utilizing the Promise.all() method with a single catch block for error handling
Using multiple catch blocks for each asynchronous operation
Handling errors outside the asynchronous operations entirely

In the scenario of multiple asynchronous operations, using Promise.all() simplifies error handling by allowing a single catch block to capture errors from any of the parallel operations. This promotes cleaner and more concise error management, making it easier to identify and address issues in the asynchronous flow. Multiple catch blocks might lead to redundancy and make the code harder to maintain.

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In the context of tree shaking, what is the significance of the "sideEffects" flag in a package.json file?

Specifies files that should be excluded from the tree-shaking process
Indicates whether the package has side effects that prevent tree shaking
Determines the priority of modules during tree shaking
Flags external dependencies for tree shaking

The "sideEffects" flag in package.json is used to inform the bundler about the side effects of a module. If set to false, it allows the bundler to perform aggressive tree shaking by eliminating unused exports. If set to true, it implies the module has side effects, and the bundler avoids tree shaking to maintain those side effects.

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In a scenario where you need to process each character of a string for a text analysis function, which loop would you choose and why?

for loop
for...in loop
forEach loop
for...of loop

The correct option is the for...of loop. This loop is specifically designed for iterating over iterable objects, such as strings, arrays, and collections. It provides direct access to the values, making it suitable for processing each character of a string. Unlike the for loop, it abstracts away the index and simplifies the code for tasks like text analysis.

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