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Start your free trialMohamed El-Damarawy
11,294 Pointsmap vs forEach
Why did we loop with map and not forEach? Does it make any difference in the context of this exercise?
I think my issue here is understanding the difference between map and forEach
1 Answer
Steven Parker
231,269 PointsThe difference between forEach
and map
is the handling of return values. The map
method builds a new array made of the return values from the callback and then returns that array, while forEach
ignores any return value from the callback and its own return is undefined.
So use map
when your callback returns a value, and you will use an array made up of those values.
David Adams
Full Stack JavaScript Techdegree Graduate 18,557 PointsDavid Adams
Full Stack JavaScript Techdegree Graduate 18,557 PointsThat makes sense! In this case, it looks like forEach() works also. Is there any reason .map() is preferable in this particular case, given (at least so far), the returned array is not being used?
Steven Parker
231,269 PointsSteven Parker
231,269 PointsWhen the return value from "map" isn't used, there's no functional difference from "forEach".