Finding length with a comparsion vs boolean. which is more preferred?

JavaScript
1

I recently finished a lab and It created few question so I am asking it here, consider following function

function checkLength(arr) {
  if (arr.length) {
    console.log(`arr has length`);
  } else {
    console.log(`array is empty`);
  }
}
checkLength([])

The question I wan to ask is if I use if(arr.length) it will give true or false based on length. Will it be a valid or which is more preferable?

2

Yes, if (arr.length) is valid when you only want to check whether an array is empty or not.

If the array is empty, its length will be 0, which is a falsy value and the condition evaluates to false.

If the length is any value other than 0, it’s a truthy value and the condition evaluates to true.

Writing it explicitly as if (arr.length > 0) is also correct (it’s just more verbose).

1 Like
3

I tend to use what I exactly mean when possible and rarely rely upon truthiness. It helps clarity and maintainability.