How do you test if a variable is Undefined, Unset, Empty, False, etc...? Do you compare to null, "", "-Select-", length() == 0?  All of the above?  (I sure hope not!!!)  Which comparison do you use for a string field type of Single Line/Multi Line/Single Select/Multi Select?  I gotta say, checking against "-Select-" is the single stupidest implementation in the Deluge scripting language.  Worse, it's not always a string.  When returning an empty/unselected dropdown value back from a function, you get an error.

alert(input.Dropdown_1); -> "-Select-"

but

string x(string y) { return input.y; } -> Error in Alert task

Is it just me or is there a complete lack of consistency?  What is going on here?  Is there someone that can clear this all up or am I alone in struggling to understand in what circumstances I need to compare against which comparisons?