Regex and JavaScript String With a Dollar ($) at the end

Question

In answering this PHP question: regex - preg_replace string, I came across something in Javascript I didn't understand. Given the following:

var s = "abc1!?d$";
alert(s.replace(/\W+/, " "));

I am alerted:

abc d$

Why is it not stripping out the last dollar?

Answer 1

Because there's an intervening word character. Try this:

alert(s.replace(/\W+/g, ' '));

Without the "g" suffix on the regex, it only makes one substitution. That handles the "!?" in the middle, but that "d" ends the sequence.

Answer 2

Because you're not using the (g)lobal flag on your matcher, so it's only matching the first consecutive sequence of non-word characters.

The following should give the result you expect:

var s = "abc1!?d$";
alert(s.replace(/\W+/g, " "));