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italiandadx2
3,566 PointsI don't understand why (sum) is used.
The function add is asking for 3 arguments one of those being a function. I understand that much... What I do not get is when the add function is invoked the function being passed as the third argument has an argument of sum...?
3 Answers
Reggie Williams
Treehouse TeacherHey italiandadx2 ! function(sum) is the third argument. The function has the argument of sum because it's anonymous and doesn't have another definition. Because we see sum as an argument of the function we know that the value passed in will be passed as well in place of the word sum inside the function
Joseph Quintiliano
Front End Web Development Techdegree Graduate 14,338 Pointsthe reason the variable 'sum' is there, is because the add's parameters is basically saying,
"(we'll take this number), (we'll take this number), and (this is where the answer/sum will be)"
JASON LEE
17,352 PointsThe function 'add' has a 3rd argument which is the anonymous function. The 'add' function calls this anonymous function and passes in a single argument (a + b). Therefore, it seems to me like an argument is passed and within it another argument. In other words, an argument within an argument. It's a tough concept for me to grasp even with this very simple example!