Add support for different syntax modes
The Curry language definition allows different case modes to disambiguate variables and other identifiers. These are:
- Prolog mode: Variables start upper case, all other identifiers lower case
- Gödel mode: Prolog mode with swapped cases
- Haskell mode: Like Haskell
- Free mode: no restrictions
Currently, the frontend parses all Curry modules in
It would be nice to add an additional case mode parameter as well as have the compiler checking if the given mode is obeyed.