My policy so far was to not use C-style syntax anymore besides the base escaped classes. C will read \t as a tab or \n for newline , but Fortran will not. So to do regex with tabs, you need to use the Fortran versions with //new_line(“”)// etc.
I’m willing to change/extend this but I would stick to being Fortran-centric, maybe those could be allowed with an extension (like cregex)?