Defining %let inside %let

[skgel]

Hello everyone

I am just getting started with macros and have been using %let for a while now. Put simply, in my program I want to have a %let command to invoke further %let commands. I want to be able to enter a relatively simple variable (i.e. year) and call other variables that are harder to remember (ID's), but which are always related. So that every year has a specific ID. Currently I am using it like this and it works:

%let year = 2020;

%let ID = 1234;
%let ID_TM1 = 5678;

%let ID_LIST = (9012, 3456, 7890);

But this requires me to look up the IDs every time I want to run another year. So, I want to look it something like this:

%let year = 2020;

%if &year = 2020 %then
   %let ID = 1234
   %let ID_TM1 = 5678
   %let ID_LIST = (9012, 3456, 7890);

This however produces the error 49, which I do not understand since there are no opening brackets.

Thank you very much!

[Kurt_Bremser · Accepted solution]

Each %LET must be terminated properly. To combine several macro statements, use the same technique used in data step programming (DO-END):

%if &year = 2020 %then %do;
   %let ID = 1234;
   %let ID_TM1 = 5678;
   %let ID_LIST = (9012, 3456, 7890);
%end;

[skgel]

Thank you very much!