Too Long; Didn't Read
Modern extensions make it easier to write code that performs badly. Map() and filter() are used in conjunction to death galore in code nowadays because “it’s so easy” But does blindly using these methods cause performance issues in your code? Let us dig in and find out. The problem is that the original array (or its filtered result) is being looped twice. Figure out how to reduce (ahem… hint, wink wink) the # of loops and the issue is resolved.