if($this) {
    do_that(); # Pretend this is indented with a tab
}

if ( $this ) {
    do_that(); # another tab
}

if($this)
{
do_that();
}

if($this)
{
    do_that();
}

if($this)
    {
    do_that();
    }

if($this)
    {
        do_that();
    }