rangeGeneratorPolyFill.js

// Sequence generator function (commonly referred to as "range", e.g. Clojure, PHP, python etc.)
const range = (start, stop, step) =>
 Array.from({ length: (stop - start) / step + 1 },
 (_, i) => start + i * step);

// Generate numbers range 0..4
range(0, 4, 1);
// [0, 1, 2, 3, 4]

// Generate numbers range 1..10 with step of 2
range(1, 10, 2);
// [1, 3, 5, 7, 9]

// Generate the alphabet using Array.from making use of it 
// being ordered as a sequence
range("A".charCodeAt(0), "Z".charCodeAt(0), 1).map((x) =>
 String.fromCharCode(x),
);
// ["A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z"]