The TypeName function is used to determine the subtype of a named variable.

There is a companion function VarType that returns the subtype number in place of the subtype name.

The output is the name of the subtype.

Code:
<% whatsubtype="This is a string subtype" %>
<% =TypeName(whatsubtype) %>

Output:
String

Code:
<% whatsubtype=12345 %>
<% =TypeName(whatsubtype) %>

Output:
Integer