Do you mean at the start of the line? If so then you might aswell just ask for $identifiers to be allowed at the start of the line, no . necessary anyway if there's nowhere for the value to be sent to. If you mean anywhere in a line then you're still left with the same problem since you'd have to use another command on the identifier, and then the command would presumably have an 'insufficient parameters' error if for example you did /echo .$identifer seeing as there's no text to be output.
