include "ConsoleWindow"

dim as Str255 s

s = ""
if s == "" then print "String is empty"
if s[0] == 0 then print "String is empty"
if len(s) == 0 then print "String is empty"

s = "Hello"
if s <> "" then print "String not empty."
if s[0] then print "String not empty."
if len(s) > 0 then print "String not empty."