Regex AND operator

Question

Based on this answer

http://stackoverflow.com/questions/469913/regular-expressions-is-there-an-and-operator

I tried the following on http://regexpal.com/ but was unable to get it to work. What am missing? Does javascript not support it?

Regex: (?=foo)(?=baz)

String: foo,bar,baz

Answer 1

It is impossible for both (?=foo) and (?=baz) to match at the same time. It would require the next character to be both f and b simultaneously which is impossible.

Perhaps you want this instead:

(?=.*foo)(?=.*baz)

This says that foo must appear anywhere and bar must appear anywhere, not necessarily in that order and possibly overlapping (although overlapping is not possible in this specific case).