retain_noerr.sas

* Gimme 10 records of a random var. ;
data fake_data ;
  do cnt = 1 to 10 ;
    randy = uniform(7376) ;
    output ;
  end ;
  keep randy ;
run ;

proc sort data = fake_data ;
  by randy ;
run ;

data explicit ;
  retain a_one a_two a_three ;
  set fake_data ;
  if _n_ = 1 then do ;
    a_one = 0 ;
    a_two = 0 ;
    a_three = 0 ;
  end ;
  if a_one   = 0 and randy ge .3  then a_one   = 1 ;
  if a_two   = 0 and randy ge .4  then a_two   = 1 ;
  if a_three = 0 and randy ge .75 then a_three = 1 ;
run ;

title1 "Vars named individually on retain." ;
proc print data = explicit ;
  var randy a_one a_two a_three ;
run ;

data wildcard ;
  retain a_: ;
  set fake_data ;
  if _n_ = 1 then do ;
    a_one = 0 ;
    a_two = 0 ;
    a_three = 0 ;
  end ;
  if a_one   = 0 and randy ge .3  then a_one   = 1 ;
  if a_two   = 0 and randy ge .4  then a_two   = 1 ;
  if a_three = 0 and randy ge .75 then a_three = 1 ;
run ;

title1 "Vars retained w/a wildcard" ;
proc print data = wildcard ;
  var randy a_one a_two a_three ;
run ;