Re: RegEx to find the index of the character '@' in an Email address

[almut]

...will work only if the given string $mail = "abcdefgh\@gmail.com"; But in my case, i will be getting the input with email address as its. Not with an escape character.

The backslash is only needed to prevent the interpolation of an array @gmail in the double quoted string literal.  The actual value in $mail won't hold the backslash, just as the input values you're expecting to handle...

That said, maybe have a look at Email::Address.