How can I override default parameters in JavaScript functions?

How can I override default parameters in JavaScript functions?

You can override default parameters by simply passing a new value when you call the function. For example, if you have a function like this: function greet(name = 'Guest') { return Hello, ${name}!; }, you can call greet('Alice') to override the default.

What if I want to use undefined to trigger the default value?

If you pass undefined as an argument, the default value will be used. For instance, greet(undefined) will return 'Hello, Guest!'. This is useful if you want to selectively use defaults.

Can I use expressions as default values?

Yes, you can use expressions! For example, function multiply(a, b = a * 2) { return a * b; } will use a * 2 as the default for b.

Are there any limitations to using default parameters?

One limitation is that default parameters are evaluated at the time of function definition, not at call time. This means they can lead to unexpected results if they depend on other parameters.