Regular Expressions: Is there an AND operator?

Question

Obviously, you can use the | (pipe?) to represent OR, but is there a way to represent AND as well?

Specifically, I\'d like to

Answer 1

Use AND outside the regular expression. In PHP lookahead operator did not not seem to work for me, instead I used this

if( preg_match("/^.{3,}$/",$pass1) && !preg_match("/\s{1}/",$pass1))
    return true;
else
    return false;

The above regex will match if the password length is 3 characters or more and there are no spaces in the password.