
What would it take to get an "-XOverloadedQuotes" flag of the same sort as the "-XOverloadedStrings" flag? I.e. "[| ... |]" would have type "Quasi m => m Exp" instead of "Q Exp" and any splices in that quotation expect the contents of that splice to have type "m Exp". (Obviously, top level splices would still have type "Q Exp" otherwise the compiler wouldn't know how to evaluate the monad.) I ran into this problem when writing a Template Haskell program in which part of it operates in a "StateT S Q a" monad instead of the usual "Q a" monad. (The "S" type stores the state of a memoization table of code fragments already generated. Without it, the code would loop infinitely when processing certain recursive structures.) It is fairly easy to declare an instance of "Quasi" for "StateT S Q", so in order to keep the code clean, I'd like to use quotations with splices in them (i.e. [| ... $( ... ) ... |] ) for expressing the generated code. However, quotations and splices are tied to the "Q" monad which means that as it is now I have to manually write "LamE ... VarP ... VarE ... etc." instead of using the much nicer quotation syntax. Michael D. Adams mdmkolbe@gmail.com