Check for valid email regexp

Here is regular expression I use to check for valid email

#
# Check whether string seems like an email
@IsEmail[email]
$result(^if(def $email && ^email.match[^^\w+([.-]?\w+)+\@\w+([.-]?[^^@]\w+)*\.[a-z]{2,4}^$][i]){1}{0})
#/IsEmail

And example of use:

^if(!^IsEmail[user@aol.com]){Invalid email}