Try the code below to have admin,demo1,system,test
DEFINE VARIABLE ctest AS CHARACTER NO-UNDO.
ctest = "demo,demo1,system,test" .
ctest = "," + ctest + "," .
ctest = replace(ctest , ",demo," , ",admin," ).
ctest = TRIM (ctest , "," ).
MESSAGE ctest
VIEW-AS ALERT-BOX...