No more switch statements in JS. Run the code here: http://jsfiddle.net/azder/tD2B8/

switcher

var s, switcher;

switcher = (function () {

    // ALWAYS
    'use strict';

    var elvis = function (value, dfault) {
        return (null === value || void 0 === value ? dfault : value);
    };

    return function (dfault, map) {

        map = elvis(map, {});

        return function (key) {
            return elvis(map[key], dfault);
        };

    };


}());


s = switcher('<unknown>', {
    1: 'a',
    2: 'b',
    3: 'c'
});

console.log(s(1), s(2), s(3), s(4), s());

s = switcher();

console.log(s(1), s(2), s(3), s(4), s());

s = switcher('constant');

console.log(s(1), s(2), s(3), s(4), s());