invalid_new.m:024: In clause for function `nc'/1:
invalid_new.m:024:   in function result term of clause head:
invalid_new.m:024:   error: undefined symbol `new c'/1.
invalid_new.m:024:   Invalid use of `new' on a constructor of type
invalid_new.m:024:   `invalid_new.c'/1 which is not existentially typed.