[houli]

This is what the backpack feature landing in GHC 8.2 will allow you to do

[runeks]

As far as I can see, backpack isn't going to solve converting between string types, unless you want to use the same string type for everything your application does (e.g. sending/receiving bytes over the network and displaying a UI component with text in it).

Or are you suggesting that we specialize the TCP receive function to only receive UTF-8 strings, so we don't have to convert when displaying to the user?

[pera]

With Backpack most of the time you would not have to think about the type of the string.

See: http://blog.ezyang.com/2016/09/the-base-of-a-string-theory-f...