Set Analysis - Combining values and variables in Element List

[#1]

Hi all - is it possible to have both a variable and a value in a set modifier?  For instance, if I know that two values in a field are to always be excluded, but want to have a third be dependent upon the user's selection, is it possible to have something like:

[Field A]-={'Value 1','Value 2',[Variable]}

I'm trying this right now, but my equation doesn't seem to work...

[sasiparupudi1]

[Field A]-={'Value 1','Value 2','$(Variable)'}

should work

[maxgro]

sum({1 <[Field A]-={'UK','USA' $(Variable)}>} Sales)

Variable

=if(GetSelectedCount([Field A])>0,

  ',' & chr(39) & concat([Field A], chr(39) & ',') & chr(39)

  )

[#4 · Accepted solution]

I'm sorry, I misspoke and didn't catch myself before reading your replies - I meant a field, not a variable.  I.E the value excluded depends on the user's selection.

[Field A]-={'Value 1','Value 2',[Field 2]}

EDIT: Got it - had to use a $ expansion.  Thanks for your help, everyone.