[].map(f) for older browsers
var map = require('array-map');
var letters = map([97,98,99], function (c) {
    return String.fromCharCode(c);
});
console.log(letters.join(''));
output:
abc
var map = require('array-map')
Create a new array ys by applying f(xs[i], i, xs) to each element in xs at
index i.
With npm do:
npm install array-map
MIT