What are some common errors when using the spread operator in JavaScript?

What are some common errors when using the spread operator in JavaScript?

Some common errors include trying to spread non-iterable objects, using it in the wrong context, or misunderstanding its shallow copy behavior.

Can you give me an example of spreading a non-iterable object?

Sure! If you try to use the spread operator on an object like this: const obj = {a: 1}; const newObj = {...obj}; it works, but if you try const newObj = {...undefined};, it will throw an error.

What about using it in function calls?

When using the spread operator in function calls, ensure the argument is an array. For example, myFunction(...[1, 2, 3]) works, but myFunction(...{a: 1}) will cause an error.

How does the spread operator handle nested objects?

The spread operator creates a shallow copy, so nested objects are still referenced. For example, const obj = {a: {b: 2}}; const newObj = {...obj}; newObj.a.b = 3; will change obj.a.b to 3 as well.