I was writing a quick script today and came across a nice use case for .apply to merge nested arrays into a single array. So I figured I’d share it.
//If we have nested arrays of depth = 1:var arr = [[1,2,3],[4,5],6];//we can flatten it by using concat and applyvar flat_arr = .concat.apply(,arr);//and check the valueconsole.log(flat_arr);//logs [1,2,3,4,5,6]
If you need a recursive (ie: infinitely nested) array flattened, check out the source for Underscore’s flatten() function, which uses concat.apply for shallow arrays.
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