function main
local cStr := "This is " + CHR(0) + " a test."
local cTest, nI, nJ, crlf := CHR(13)+CHR(10)

   // Test various string operators.
   OUTSTD (LEN(cStr))
   OUTSTD (cStr)
   OUTSTD (UPPER (cStr))
   OUTSTD (LOWER (cStr))
   OUTSTD (CHR (13) + CHR (10))
   OUTSTD (ASC (SUBSTR (cStr, 8)))
   OUTSTD (ASC (SUBSTR (cStr, 9)))
   OUTSTD (ASC (SUBSTR (cStr, 10)))
   OUTSTD (crlf)
   OUTSTD (crlf)
   OUTSTD (crlf)
   OUTSTD (">")
   OUTSTD (LEFT (cStr, 8))
   OUTSTD("<")
   OUTSTD (crlf)
   OUTSTD (">")
   OUTSTD (RIGHT (cStr, 8))
   OUTSTD("<")
   OUTSTD (crlf)
   OUTSTD (ISDIGIT ("9"))
   OUTSTD (crlf)
   OUTSTD (ISDIGIT ("9A"))
   OUTSTD (crlf)
   OUTSTD (ISDIGIT ("AA"))
   OUTSTD (crlf)
   OUTSTD (ISDIGIT ("A"))
   OUTSTD (crlf)
   OUTSTD (crlf)
   cTest := "   " + CHR (0) + "ABC" + CHR (0) + "   "
   OUTSTD (crlf)
   OUTSTD (">")
   OUTSTD(LTRIM (cTest))
   OUTSTD("<")
   OUTSTD (crlf)
   OUTSTD (">")
   OUTSTD(TRIM (cTest))
   OUTSTD("<")
   OUTSTD (crlf)
   OUTSTD (">")
   OUTSTD(ALLTRIM (cTest))
   OUTSTD("<")
   OUTSTD (crlf)
   OUTSTD (crlf)
   OUTSTD (crlf)
   OUTSTD (">")
   OUTSTD (REPLICATE ("!", 32))
   OUTSTD("<")
   OUTSTD (crlf)
   OUTSTD (">")
   OUTSTD (SPACE (32))
   OUTSTD("<")

   // Test string copying.
   cTest := cStr
   OUTSTD (crlf)
   OUTSTD (cStr)
   OUTSTD (crlf)
   OUTSTD (cTest)
   OUTSTD (crlf)
   OUTSTD (crlf)

   // Test string concatenation.
   cTest += cStr
   OUTSTD (crlf)
   OUTSTD (cStr)
   OUTSTD (crlf)
   OUTSTD (cTest)
   OUTSTD (crlf)
   OUTSTD (crlf)

   // Test the string comparison operators in the HVM.
   StrTest ("ABC", "ABC")
   StrTest ("ABC", "ABCD")
   StrTest ("ABCD", "ABC")
   StrTest ("ABC", "DEF")
   StrTest ("ABC", "DEFG")
   StrTest ("ABCD", "DEF")
   OUTSTD (crlf)
   OUTSTD (crlf)
return nil

function StrTest (Str1, Str2)

   OUTSTD (CHR(13)+CHR(10)+CHR(10))
   OUTSTD (Str1)
   OUTSTD (", ")
   OUTSTD (Str2)
   OUTSTD (" == ")
   OUTSTD (Str1 == Str2)
   OUTSTD (", != ")
   OUTSTD (Str1 != Str2)
   OUTSTD (", < ")
   OUTSTD (Str1 < Str2)
   OUTSTD (", <= ")
   OUTSTD (Str1 <= Str2)
   OUTSTD (", > ")
   OUTSTD (Str1 > Str2)
   OUTSTD (", >= ")
   OUTSTD (Str1 >= Str2)

   OUTSTD (CHR(13)+CHR(10))
   OUTSTD (Str2)
   OUTSTD (", ")
   OUTSTD (Str1)
   OUTSTD (" == ")
   OUTSTD (Str2 == Str1)
   OUTSTD (", != ")
   OUTSTD (Str2 != Str1)
   OUTSTD (", < ")
   OUTSTD (Str2 < Str1)
   OUTSTD (", <= ")
   OUTSTD (Str2 <= Str1)
   OUTSTD (", > ")
   OUTSTD (Str2 > Str1)
   OUTSTD (", >= ")
   OUTSTD (Str2 >= Str1)

return nil