Using the IN operator not working?

[SasStatistics]

I have the following code (not identical but it captures the question): 

%let country = SE;

%IF &country. in (SE NO USA) %THEN %DO; 
	data MyTable1; 
	run; 
%END;

%IF &country. = UK %THEN %DO; 
	data MyTable2; 
	run; 
%END;

Running this code yields the error: 

ERROR: Required operator not found in expression: SE in (SE NO USA) 
ERROR: Skipping to next %END statement.

Any ideas why this error occurs and how I can solve it? 

[Tom · Accepted solution]

If you want to use IN as an operator in macro code you need to tell it so.

Use the MINOPERATOR option and the MINDELIMITER= option to tell SAS that you want to use IN as an operator.

If you are using this inside a macro definition use the MINOPERATOR and MINDELIMITER= options on the %MACRO statement.

165   options minoperator mindelimiter=' ';
166
167   %let country = SE;
168
169   %IF &country. in SE NO USA %THEN %DO;
170     %put &=country in list.;
COUNTRY=SE in list.
171   %END;