Regular Expression to search longest word in a string

Question

I have a string:

var str = "Lorem ipsum dolor sit amet, consectetur adipiscing elit";

Is there a way to find the longest word in a string using regex? This will prevent me to split the string into words and then looping through all of them.

Possibly if I can use it in JavaScript as:

str.search(/regex/); // should return 28 (position of word 'consectetur')

Thanks.

Answer 1

As already mentioned in comments, this is not possible with a regex only solution. And nearly all solutions I can think of; would still need you to slice the string to words. The smallest solution you can use would be:

var x = str.match( /\w+/g );
var y = x.map( function(t) { return t.length } );
var z = str.indexOf( x[y.indexOf( Math.max.apply(Math, y) )] );

Answer 2

Check this Update LINK

JS Code:

 var str = "Lorem ipsum dolor sit amet, consectetur adipiscing elit";
    str = str.replace(/[^A-Za-z\s]/g, " ");
        var maxoffset = 0, maxlen=0, wordoffset = 0;
        for (var i = 0; i < str.length; i++) {
            if (str[i] == " ") {
                wordoffset = i + 1;
            }
            if (i - wordoffset + 1> maxlen) {
                maxoffset = wordoffset;
                maxlen = i - wordoffset + 1;
            }
        }
        return str.substring(maxoffset, maxoffset + maxlen);

Answer 3

I know this is old, but here is my solution that I did not see posted.

Obv this is the fastest solution posted, albeit a little late.

Accomplish the task using Array.prototype.reduce with String.prototype.match.

     text.match(/\w+/g).reduce( (p,c) =>
       c.length > p.length ? c : p
     ,'');