In what scenarios is it more beneficial to use tagged template literals over regular template literals?
- When dynamic string processing or transformation of the template is required.
- When simple string concatenation suffices for the task.
- Tagged template literals are only used in specific edge cases.
- When you need to create a static string with fixed content.
Tagged template literals provide a powerful mechanism for customizing string output, making them beneficial in scenarios where dynamic content manipulation is necessary, such as in i18n (internationalization) or code generation. Regular template literals are simpler and more suitable for static strings.
How does the yield* keyword differ from yield in a generator function?
- Both are equivalent
- yield* is used for delegating to another generator or iterable
- yield is used for async operations
- yield* is used for synchronous operations
The yield* keyword in a generator function is used for delegating to another generator or iterable. It allows you to compose generators and is often used for iterating over iterable objects within the generator function. On the other hand, yield is used to pause the generator and yield a value to the caller.
Composition in ES6 involves creating objects by combining multiple __________ that provide functionality.
- Promises
- Objects
- Prototypes
- Modules
Composition in ES6 involves creating objects by combining multiple objects that provide functionality. This promotes a modular and reusable code structure by assembling smaller pieces to form more complex objects.
When iterating over a Map object with a for...of loop, each iteration returns an array where the first element is the _______ and the second is the value.
- key
- index
- property
- length
In a Map object, the first element of the array returned during iteration represents the key, and the second element represents the corresponding value.
In functional composition, the output of function ______ becomes the input of function ______.
- Output, Input, Result, Transformation
- Transformation, Input, Output, Composition
- Result, Transformation, Input, Output
- Composition, Result, Output, Input
In functional composition, the output of one function serves as the input for the next one. This is a key concept in functional programming, where functions are chained together to perform a series of transformations on data.
Consider a library with multiple utility functions; how would you structure the exports to optimize for tree shaking?
- export function util1() {} export function util2() {}
- export { util1, util2 }
- export default { util1, util2 }
- export const util1 = () => {}; export const util2 = () => {};
To optimize for tree shaking, individually exporting functions (export function util1() {}) allows dead code elimination, ensuring only the used functions are included in the final bundle.
In object methods, using arrow functions can lead to issues when relying on the this keyword, as it does not bind its own this, but inherits it from the ________ scope.
- Parent
- Global
- Lexical
- Block
Arrow functions inherit the this value from their lexical scope, which means the scope in which they were defined. This can lead to unexpected behavior when used in object methods.
In Node.js, ES6 Modules have a different file extension (_________) compared to CommonJS modules (.js).
- .mjs
- .es6
- .es
- .node
Node.js uses the .mjs file extension for ES6 modules to differentiate them from CommonJS modules that typically use the .js extension. This helps Node.js to identify the module type and apply the appropriate module loading mechanism.
Can a static method in a parent class be overridden in a child class?
- Yes
- No
- Depends on the method implementation
- Only if explicitly declared as override
Yes, a static method in a parent class can be overridden in a child class. However, it's important to note that static methods are associated with the class itself rather than instances, and the child class can provide its own implementation of the static method, effectively overriding the one in the parent class.
Can default parameters be expressions or function calls?
- No, only primitive values are allowed
- Yes, any valid expression or function call is allowed
- Only function calls are allowed
- Only arrow function expressions are allowed
Yes, default parameters in ES6 can be expressions or function calls. This enables dynamic default values based on the evaluation of expressions or the result of function calls. It provides flexibility and allows for more sophisticated default values in function parameters.