Question

Given the following array:

var things = ['sandwich', 17, '[e-mail]', 3, 'horse', 'octothorpe', '[e-mail]', '![e-mail]']; 

Sort the array into three others, one of numbers, one of strings, and one of valid email addresses. Discard the invalid address.

Answer 1

var emails = [], strings = [], numbers = [];

things.forEach(function (e) {
    if (typeof e == "string") {

        if (e.indexOf("@") != -1) { // "looks" like an email if it contains @
           if (isEmail(e)) emails.push(e); // push if it is a valid email
        }

        else strings.push(e);
    }

    else if (typeof e == "number") {
       numbers.push(e);
    }
 });

function isEmail(str) { return /** true if str is a valid email **/ }

I’ll leave it up to you to come up with a correct isEmail function.