*---Macro exist checking the existence of a SAS data set;

%macro exist( sds );

%global exist;

%if %sysfunc(exist(&sds)) %then

%do;

%let exist=YES;

%put "There is a data set named &sds" ;

%end;

%else

%do;

%let exist=NO;

%put "The data set &sds doesn't exist" ;

%end;

%mend exist;

*--Run macro;

%exist( sashelp.usstate );

%exist( sashelp.uspop );