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JavaScript

Marcel Carey
Marcel Carey
2,890 Points
Posted by Marcel Carey
Marcel Carey
2,890 Points

When using for loops, whats the difference between using .length or just a boolean value

So I have this ex. let numbers = [] for(let i = 0; i < numbers.length; i++){ return doSomething } vs let numbers = [] for(let i = 0; i < 0; i++){ return doSomething }

1 Answer

Adam Szlag
Adam Szlag
15,322 Points

In case of: for( let i = 0; i < numbers.length; i++) You run the loop as many times as there are values in array numbers[], The part "i < numbers.length" stands for condition to run the loop, if it's true the loops run, if it's false the loop stops. If you use: for(let i = 0; i < 0; i++) and array isn't empty the for loop won't run even once, because before you execute code in {} your condition (i<0) is false and loop ends.

It is a good idea to loop certain numer of times in this case as many times as arguments in numbers[] array.