I have a form variable whose value is being passed to a DTML method upon form submission. In this DTML method, I use the form variable as input to a <dtml-in>. When this form variable is passed as a list(i.e. it contains multiple values), everything works fine. However, when this form variable is passed as a string(i.e. it contains a single value), <dtml-in> complains that it is being passed an input of the wrong type. Is there a way to detect whether this form variable is a list or string? Using the len function doesn't work because len works on both strings and lists. One solution I have figured out uses a HTML hidden variable to set the form variable to a default value. This guarantees that the form variable is always a list since a minimum of 2 values are passed upon form submission. However, this is a hack and I'd rather use something more elegant. Any help would be greatly appreciated. Thanks. - Asad