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JavaScript JavaScript Array Iteration Methods Array Manipulation Remove Array Items with filter()

Fat Arrow Refactor

Hello All,

Wondering how to refactor this if possible

const numbers = [1,2,3,4,5,6,7,8,9,10];

numbers.filter(number => number % 2 === 0);

I'm wondering since I have number => number can I do something fancy with number so I wont have to write it twice (thinking ES6)

1 Answer

Steven Parker
Steven Parker
231,184 Points

This is already compact. The first "number" (left of the arrow) identifies it as the argument, the second one shows what should be done with it in the function.

If you don't feel clarity is seriously compromised, you can make it a bit more concise with a single-letter argument and a logical test instead of an equality comparison:

numbers.filter(n => !(n % 2));