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Ingrid Bardales
10,616 Pointswhich variable console's out
What will console log out in the following code?
var person = "Jim";
function whosGotTheFunc() { var person = "Andrew"; }
person = "Nick";
whosGotTheFunc();
console.log(person);
The answer to this quiz question is "Jim" and i thought it would have been "Nick". Here's my logic: Jim is initialized in the global scope, Andrew is initialized in the local scope of the fuction, Nick is now the new value of the var "person" the function is called and the value is Andrew, console.log(person) --this should console out the new value of Nick.
Ok pleeeease, tell me where i went wrong, this is eating at me, thanx in advance for your help!!! Ingrid
5 Answers
Joy Kesten
Treehouse Guest TeacherI got "Nick" as the correct answer when the var keyword was written before the variable person inside the function because in this case it's making a new variable inside the function.
function whosGotTheFunc() {
var person = "Andrew";}
I got "Andrew" as the correct answer when var was not included before person inside the function because in this case it thinks you're trying to assign a new value to the global variable person.
function whosGotTheFunc() {
person = "Andrew";}
When a variable is defined in the global scope and then assigned the same named variable inside a function using the var keyword + variable name+ value, the variable inside the function is only going to be accessible inside the function.
In short, by defining the variable in the function, you do not affect the global variable. If you leave off the var you're reassigning the global variable.
Matthew Greenberg
8,173 PointsThe var declaration inside of the function is whats throwing you off.
function whosGotTheFunc() { var person = "Andrew"; }
This function creates a new scope in which the var person is defined and set to andrew. This does not affect the global scope person.
function whosGotTheFunc() { person = "Andrew"; }
this function creates a new scope as well; however, instead of defining a variable person and assigning it the string "Andrew"... we are setting the global variable person to andrew.
So in short... Unless the variable is defined first inside of the function with the 'var' keyword, you are writing to the global namespace.
Ingrid Bardales
10,616 PointsThanks Matthew,...but here is what i thought"
OK, I know var person ="Jim" is declared on the global scope and i also understand that the var person = "Andrew" inside the function is not going to called because it is local to the function but then after the function, you have person = "Nick", I thought Nick would then replace "Jim" .
Joy Kesten
Treehouse Guest TeacherIngrid Bardales When I took the test, Nick does replace Jim when var is included. Andrew is the answer when var is not included.
Ingrid Bardales
10,616 Pointsoh, when i took the test, i clicked on Nick and it was the wrong answer. then i took it again and got Jim as the right answer..maybe a glitch.
Joy Kesten
Treehouse Guest Teacherweird. Sorry about that. But good work sticking with it and seeking help :)
Ingrid Bardales
10,616 Pointsthanks guys for your help, it appears as if there was a little glitch when i took the quiz! Thanx again!
Ingrid Bardales
10,616 PointsIngrid Bardales
10,616 PointsThanks Joy,...but here is what i thought"
OK, I know var person ="Jim" is declared on the global scope and i also understand that the var person = "Andrew" inside the function is not going to called because it is local to the function but then after the function, you have person = "Nick", I thought Nick would then replace "Jim" .