Have you tried just ``? I don't see what you would need a comma for. However, it looks like you need to define `$one $two $three` variables to use tal.
– BergiAug 11 '14 at 22:49
ExpressionError: Not a valid path-expression. That is what it tells me when I have two variables there.
– Josh BirdwellAug 11 '14 at 22:53