why end of recursion returns undefined

Question

just a quick question on recursion. I'm trying to make a function that displays the integers in a a range. It prints all the integers but when it gets to the end it just shows undefined.

Here's the code.

function range(start, end) {
    var _start = start;
    if (_start < end) {
        console.log(_start);
        range(start + 1, end);
    } else {
        console.log(_start)
    }
}

I think that what you are trying to do is a generator function. In that case you have to return values with the keyword `yield`. You can do it is you use ES 2015. — dlopez, Jun 03 '16 at 12:38
@RejithRKrishnan yes. just using the console to get the basics of the language down — , Jun 03 '16 at 12:40

score 4 · Answer 1 · edited Jun 03 '16 at 12:43

4

By default javascript functions return undefined unless you explicitly return something.

edited Jun 03 '16 at 12:43

Bergi

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answered Jun 03 '16 at 12:38

AB Udhay

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why end of recursion returns undefined

1 Answers1