javascript function returning undefined even though value display in console.log

Question

I've got this really annoying issue where a function returning a value of undefined every time even though the console.log() always shows that there is a value when getting into the first if statement

This is my function

function getElementIdentifier(elem, domSelector) {
    if(elem.getAttribute('id') !== null) {
        console.log('here');

        return elem.id + ' ' + domSelector;
    } else {
        getElementIdentifier(elem.parentNode, elem.tagName + ' ' + domSelector);
    }
}

This is how I call it

getElementIdentifier(elem, '');

Heres a fiddle to replicate it. http://jsfiddle.net/wqCSn/5/ (thanks @adeneo)

you miss return state in second branch and you check elem.getAttribute('id') but try to return elem.id -- do next return '' + elem.id + ' ' + domSelector; — Vasiliy vvscode Vanchuk
– Vasiliy vvscode Vanchuk, Commented Mar 15, 2014 at 15:15
@VasilVanchuk I'm calling itself so dont need a return this. — Tom Maton
– Tom Maton, Commented Mar 15, 2014 at 15:18
Why would it return the result when it's recursive, it returns something if the condition is met on the next iteration. — adeneo
– adeneo, Commented Mar 15, 2014 at 15:23

Vasiliy vvscode Vanchuk · Accepted Answer · 2014-03-15 15:38:23Z

3

Your function does not return value if call self recursively. You should to add return statement ro alternative branch of algorithm

function getElementIdentifier(elem, domSelector) {
    if(elem.getAttribute('id') !== null) {
        return elem.id + ' ' + domSelector;
    } else {
        return getElementIdentifier(elem.parentNode, elem.tagName + ' ' + domSelector);
    }
}

answered Mar 15, 2014 at 15:38

Vasiliy vvscode Vanchuk

7,1992 gold badges24 silver badges46 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Charlie Affumigato · Accepted Answer · 2014-03-15 15:34:22Z

1

hmmmm... try this:

function getElementIdentifier(elem, domSelector) {
 if(elem.getAttribute('id') !== null) {
    console.log('here');

    return elem.id + ' ' + domSelector;
 } else {
 //return the recursion returned value (sounds like inception) but
 //you are expecting a value from this function... 
    return getElementIdentifier(elem.parentNode, elem.tagName + ' ' + domSelector);
 }
}

edited Mar 15, 2014 at 15:34

answered Mar 15, 2014 at 15:28

Charlie Affumigato

1,0271 gold badge8 silver badges10 bronze badges

Collectives™ on Stack Overflow

javascript function returning undefined even though value display in console.log

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related