{if true eq isset( $username ) and false eq $is_logged and false}
{if true eq isset( $username )
and false eq $is_logged and false}

{if true eq isset( $username ) and $boolLoggedIn}
    Hello {$username}
{/if}

{if true eq isset( $username )}
    {assign var=username value=$fname}
{/if}

{(if|/if)(.)*(?<=})