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Konrad Dziekonski
7,798 Pointslittle modification
Hello,
I have tried to modify Daves code a little by defining third parameter in the getArea function:
function getArea(width, length, unit) { var area = width*length; var unit = 'm2'; return area + "" + unit; }
console.log(getArea(10, 20, unit));
but the console is returning: Uncaught reference error: unit is not defined at random.js:7
could you please explain why is it not working? I thought that if I would store a value of string 'm2' in a variable called unit I could use it than in a way like the function knows that it has to multiply width by length. But hmm why is it stored in variable "area" but the keyword "area" has not been used, what for was it stored in this variable?
I have also tried to delete the third parameter from the function:
function getArea(width, length) { var area = width*length; var unit = 'm2'; return area + "" + unit; }
console.log(getArea(10, 20, 'm2'));
but left it in the console log and it appeared in the console log screen, so why was it necessary to declare the third parameter - unit?
if that make sense at all... i mean my qustion ;] thanks
Henry Bown
30,839 PointsHenry Bown
30,839 PointsIf you're passing unit as one of the parameters, you don't need to set it as a variable separately.
This snippet will output "200 m2" to the console.
This will also output '200 m2'
The reason you're getting this error is due to defining the variable inside the function. The code that effectively is running is similar to:
So at the time that it is calling the variable, it isn't defined.