Nice work. But as far as I can see this only works for the intrinsic Fortran datatypes, i.e. the various kinds of integers and reals. Any chance for extending this to user-defined types? Looking at the code, all functionality has been repetitively implemented for each datatype -- I hope this has not been done manually, but with a code generator? If so, could the generator be extended to process user-defined datatypes?

It's really unfortunate that modern Fortran has no facilities for generic programming. That's why I'm personally moving more and more to Julia...