OK, you were right :) I made a small change -- instead of namiing my new class <generalized-array>, I simply named it <array>, so that the smob name overlaps with the class name. I don't know if it's a proper programming style, but it's simple and it works.
There is, however, another problem that I've observed. I don't know if it is caused by my modification, but both array-shape and array-dimensions return the following error: While compiling expression: ERROR: In procedure vector-length: Wrong type argument in position 1 Other than that, I could send the patch (if I only knew how to generate it). Best regards, M. 2011/9/5, Panicz Maciej Godek <godek.mac...@gmail.com>: > I've been trying to add the superclass. > Adding it to <vector> and <bytevector> turned out > to be extremely simple, but the problem emerged > when I was trying to generalize the <array> class. > > The thing is that <array> is implemented as a smob, > and that there is no easy way to add a superclass > to a class created from smob. > > I can think of a number of ways of making > a workaround, but all of them are nasty. Each > of them will require the modification of > goops.c: create_smob_classes. > > The first way would be to check whether > !strcmp (SCM_SMOBNAME (i), "array") > and to behave appropriately when it happens. > > But that would be just ugly. > > The other two ways that come to my mind would be: > 1. to modify the type `scm_smob_descriptor', adding > SCM supers; /* list of superclasses */ > > or, equivalently > 2. to add a new global array, > SCM_API SCM smob_supers[MAX_SMOB_COUNT], such > that their default would either be SCM_EOL, or > scm_list1(scm_class_top). > > The other idea would be to mess with > scm_sys_inherit_magic_x and add a superclass > after the creation of "<array>", but that doesn't > sound too sound (at least for as long as this action > is undocumented) > > So to me it seems that adding the <generalized-array> > (or however should it be called) that would be the > ancestor of "array" requires some changes in the > guile API. I wouldn't do it without the overall approval. > > Best regards > M. > > > 2011/9/3, Andy Wingo <wi...@pobox.com>: >> Hi Panicz, >> >> On Fri 02 Sep 2011 21:53, Panicz Maciej Godek <godek.mac...@gmail.com> >> writes: >> >>> In other words, classes <vector>, <uvec> and <array> have nothing in >>> common, which requires me to triple the number of methods that could >>> accept any of these types. >> >> We should fix this. We can probably do it in 2.0. Interested in >> sending a patch? >> >> Currently this stuff is in C, unfortunately. Perhaps it should move to >> Scheme at some point, but if you just wanted to add an <array> or >> <generalized-vector> superclass, see goops.c. Look for the <uvec> stuff >> and follow the patterns. >> >> Andy >> -- >> http://wingolog.org/ >> >
