Like you could!

I wrote a program the has only one symbol of each UPPER and lower case assemble value! It writes itself and discards the program. It can never be virus-ed but the guv won't let me protect it!

So you get this, the program interprets what you say into an executable program you direct, in toto! The program doesn't exist until you need it and it'll write itself, execute and disappear. Oh it also has a complete dictionary and thesaurus and corrects as you command!