// Generate a random 4-bit hex digit
randHexDigit = function
	n = floor(rnd * 16)
	hex = "0123456789abcdef"
	return hex[n]
end function

// Generate a random 4-character hex block
randHexBlock = function(len)
	s = ""
	for i in range(0, len - 1)
		s = s + randHexDigit()
	end for
	return s
end function

// Entry point
generateUUIDv4 = function
	part1 = randHexBlock(8)
	part2 = randHexBlock(4)
	part3 = "4" + randHexBlock(3)    // UUID version 4
	part4 = randHexDigit()
	part4 = "89ab"[floor(rnd*4)] + randHexBlock(3)  // variant bits
	part5 = randHexBlock(12)
	return part1 + "-" + part2 + "-" + part3 + "-" + part4 + "-" + part5
end function