When implementing code splitting using dynamic imports, large bundles are broken into smaller __________.
- Components
- Chunks
- Fragments
- Segments
Code splitting is the technique of breaking large bundles into smaller chunks, and in ES6, this is achieved through dynamic imports, creating separate chunks. Code chunks are often referred to as "chunks" in this context.
How can default parameters in ES6 simplify recursive function calls?
- Default parameters in ES6 allow for the specification of default values when a function is called without providing certain arguments. In recursive functions, this simplifies the base case handling by providing default values when no explicit argument is passed.
- The use of default parameters in recursive functions helps to eliminate the need for explicit base case checks, as the default values act as implicit base cases. This can lead to more concise and readable recursive function implementations.
- ES6 default parameters enable the definition of recursive functions with fewer parameters, reducing the complexity of function signatures and making recursive calls more intuitive.
- Utilizing default parameters in recursive functions facilitates the creation of more generic and adaptable recursive algorithms, allowing for greater flexibility in handling different input scenarios.
Default parameters in ES6 simplify recursive function calls by providing default values, reducing the need for explicit base case handling. This results in cleaner and more concise code, enhancing the readability of recursive functions.
Question 1: Consider a project with both Node.js and browser targets. How would you use the ES6 module resolution to handle environment-specific code?
- Use relative paths
- Use absolute paths
- Utilize environment variables
- Utilize conditional imports
In a project targeting both Node.js and browsers, you can use conditional imports to handle environment-specific code. This allows you to import different modules based on the execution environment, improving code maintainability and adaptability. By leveraging the ES6 module system's flexibility, you can create modular and environment-aware code.
When multiple asynchronous tasks are independent of each other, use await with __________ to run them concurrently.
- Promise.all
- Promise.race
- Promise.parallel
- Promise.concurrent
To run multiple independent asynchronous tasks concurrently, use await with Promise.all. This ensures all tasks are completed before proceeding.
In the context of Promises and AJAX, how does async/await improve error handling compared to .then() and .catch()?
- It simplifies error handling by using try-catch blocks.
- It requires additional error-checking code.
- It has no impact on error handling.
- It replaces error handling with callbacks.
Async/await improves error handling by allowing the use of try-catch blocks, making code more readable and maintaining a synchronous look and feel. This results in cleaner and more maintainable code, enhancing the developer's ability to handle errors effectively.
When building a new object that combines properties from several sources, how can the spread operator be used effectively?
- Merge properties using the { ...source1, ...source2 } syntax
- Combine properties using the Object.assign() method
- Concatenate properties using the + operator
- Extend properties using the extends keyword
The spread operator (...) is commonly used to merge properties from multiple sources into a new object. Using { ...source1, ...source2 } allows you to create a new object with properties from both sources effectively.
What character is used to define a template literal in JavaScript?
- Backtick (`)
- Dollar sign ($)
- Hash (#)
- Exclamation mark (!)
In JavaScript, a template literal is defined using the backtick (`) character. It allows for easy string interpolation and multiline strings, making it a powerful feature for string formatting.
What is the return value when accessing a Map object's element with a non-existing key?
- undefined
- nan
- KeyError
- FALSE
When accessing a non-existing key in a Map, the result is undefined. This behavior is different from objects, where accessing a non-existing property returns undefined.
If you need to access both the index and value in an array using for...of, use __________ to convert the array into an iterable of index-value pairs.
- Object.entries()
- Array.entries()
- indexValuePairs()
- iterable()
If you need to access both the index and value in an array using for...of, use Array.entries() to convert the array into an iterable of index-value pairs. This allows you to destructure the pairs in the for...of loop, providing both index and value in each iteration.
JavaScript’s __________ nature allows it to perform non-blocking operations despite being single-threaded.
- Synchronous
- Asynchronous
- Parallel
- Multithreaded
The correct option is Asynchronous. JavaScript's asynchronous nature is a key feature that enables it to handle multiple tasks concurrently without blocking the main thread. This is achieved through mechanisms like callbacks, Promises, and async/await, making it suitable for building responsive and efficient applications.