JSFiddle - React, Tailwind, and code Playground

by David Thomas

JavaScript

function keyMap(start, stop) {
    var startFrom, stopAt, o = {};
    switch (typeof start) {
        case 'string':
            startFrom = start.charCodeAt(0);
            break;
        case 'number':
            startFrom = start;
            break;
        default:
            return '';
    }
    switch (typeof stop) {
        case 'string':
            stopAt = stop.charCodeAt(0);
            break;
        case 'number':
            stopAt = stop;
            break;
        default:
            stopAt = start.length > 1 && typeof start === 'string' ? start.charCodeAt(1) : startFrom;
            break;
    }

    for (var i = startFrom, len = stopAt + 1; i < len; i++) {
        o[String.fromCharCode(i)] = i;
    }
    return o;
}

var map = keyMap('s');
console.log(map, map['s'], map.s);