On Wednesday, 14 January 2015 at 14:54:09 UTC, Laeeth Isharc
wrote:
In the hierarchy example above (c++ hdf hierarchy link), by
using UFCS to implement the shared methods (which are achieved
by multiple inheritance in the c++ counterpart) did you mean
something like this?
// id.d
struct ID { int id; ... }
// location.d
struct Location { ID _id; alias _id this; ... }
// file.d
public import commonfg; // ugh
struct File { Location _location; alias _location this; ... }
// group.d
public import commonfg;
struct File { Location _location; alias _location this; ... }
// commonfg.d { ... }
enum isContainer(T) = is(T: File) || is(T : Group);
auto method1(T)(T obj, args) if (isContainer!T) { ... }
auto method2(T)(T obj, args) if (isContainer!T) { ... }
I guess two of my gripes with UFCS is (a) you really have to
// another hdf-specific thing here but a good example in
general is that some functions return you an id for an object
which is one of the location subtypes (e.g. it could be a File
or could be a Group depending on run-time conditions), so it
kind of feels natural to use polymorphism and classes for
that, but what would you do with the struct approach? The only
thing that comes to mind is Variant, but it's quite meh to use
in practice.
Void unlink(File f){}
Void unlink(Group g){}
For simple cases maybe one can keep it simple, and despite the
Byzantine interface what one is trying to do when using HDF5 is
not intrinsically so complex.
So your solution is copying and pasting the code?
But now repeat that for 200 other functions and a dozen more
types that can be polymorphic in weirdest ways possible...
