Cheks if a SAS variable exists

varExist.sas

***********************************************************************;
* Projekt           : macropg
*
* Program name      : VarExist.sas
*
* Path              : /Y/nyfls/Statistikprogrammer/Macroprg/varExists.sas
*
* Author            : Rud Faden
*
* Date created      : 2018-05-14 12:50
*
* Comments          : Tjekker om en given variable findes
|**********************************************************************;

%macro varexist(ds, var);
    %local rc dsid;
    %let dsid = %sysfunc(open(&ds));

	%if &DSID = 0 %then %do;
		%put %sysfunc(sysmsg());
		%let varexist = .;
		%goto mexit;
	%end;

    %if %sysfunc(varnum(&dsid, &var)) > 0 %then %do;
        %let varexist = 1;
        %put NOTE: Var &var exists in &ds;
    %end;
    %else %do;
        %let varexist = 0;
        %put NOTE: Var &var not exists in &ds;

    %end;

    %let rc = %sysfunc(close(&dsid));
%mexit: &varexist.
%mend varexist;