What are the best practices for using foreach and map in JavaScript?

What are the best practices for using foreach and map in JavaScript?

When using foreach, it's best for executing a function on each element without returning a new array. Use map when you need to transform elements and return a new array.

Can you give me an example of when to use each?

Sure! Use foreach for logging each item in an array, like array.forEach(item => console.log(item));. Use map for transforming data, like const doubled = array.map(num => num * 2);.

Are there performance differences between them?

Yes, map can be more efficient for transformations since it returns a new array directly, while foreach is better for side effects without needing a return.

What about using them with asynchronous functions?

For asynchronous operations, prefer using map with Promise.all to handle promises effectively, as foreach does not wait for promises to resolve.