Simon Peyton-Jones wrote:
If you want validation of literal strings, then TH quasiquotes are the way to go:
I agree. OverloadedStrings is, in effect, an unsafe replacement for quasiquotes. People find OverloadedStrings easier to use than quasiquotes, so its use in that way is becoming popular. What we need is a mechanism for allowing string literals to have the type Text or ByteString instead of String. I do not want to be forced to turn on UnsafeQuasiQuotes every time I need a string literal. So in my opinion, OverloadedStrings is the wrong mechanism for providing Text and ByteString literals. Alternatives that have been suggested: o A hard-coded pragma to specify the type of string literals in a module as Text or ByteString. o An extra method of IsString, of type QuasiQuoter, that runs at compile time in a monomorphic context. o As above, but only check syntax at compile time in a monomorphic context. That allows a simpler API, without requiring any TH knowledge in most cases. Thanks, Yitz