js,ruby,elixir,python3對比

	javascript	ruby	python3	elixir
Array map	map	map
Array filter	filter	select
Array reduce	reduce	reduce
Array append		arr << item	arr.append(item)
Array length		arr.length	len(arr)
String include	includes	include?		Enum.member?
String slice	substring(n, m)	str[n … m]	str[n:m]
Array元素異構	✔	✔	✔