javascript array flattener

flatten.js

'use strict';

// es6
const flatten = (a) => (!Array.isArray(a)) ? [ a ] : a.reduce((f, i) => f.concat(flatten(i)), []);

// es5
/*
function flatten(ary) {
  if (!Array.isArray(ary))
    return [ ary ];

  return ary.reduce(function(flat, item) {
    return flat.concat(flatten(item));
  }, []);
};
*/

export default flatten;