One downside of this is that I can't figure out how to create an empty array of default-implementation struct-organized objects. The normal way to do this in Matlab seems to be `repmat(MyObject, [0 0])`, but without repmat, I can't do that.

This means that for default-implementation struct-organized classes, I can't represent the empty set with the appropriate type, and have to fall back on using double `[]`, which doesn't have the same operations as the class, so clients have to include special-case logic for empties.

It seems that cat, its [...] equivalent, reshape, and repmat are not working for classdef objects. This is a bummer, because these are kind of basic elements of OOP M-code programming if you're not going to go all the way and make planar-organized objects.

Lets's say I have a class packajoozle.internalVersion with properties string, elements, and suffix. https://github.com/apjanke/octave-packajoozle/blob/679b4afc3e5e706f6b9ca259705102d0edc077e6/inst/%2Bpackajoozle/%2Binternal/Version.m It does not override size, cat, reshape, numel, or any of the other structural methods; it is a regular struct-organized object.

Trying to do [...], reshape, or repmat on it produces an Octave error.

>> addpath('~/local/repos/octave-packajoozle/inst')
>> ver = packajoozle.internal.Version('1.2.3')
ver =
1.2.3

>> [ver ver ver]
warning: struct: converting a classdef object into a struct overrides the access restrictions defined for properties. All properties are returned, including private and protected ones.
warning: struct: converting a classdef object into a struct overrides the access restrictions defined for properties. All properties are returned, including private and protected ones.
warning: struct: converting a classdef object into a struct overrides the access restrictions defined for properties. All properties are returned, including private and protected ones.
error: octave_base_value::parent_class_name_list(): wrong type argument 'object'
>> repmat(ver, [0 0])
error: octave_base_value::resize (): wrong type argument 'object'
error: called from
    repmat at line 108 column 9
>> repmat(ver, [4 1])
error: octave_base_value::reshape (): wrong type argument 'object'
error: called from
    repmat at line 111 column 9
>> reshape(ver, [1 1])
error: octave_base_value::reshape (): wrong type argument 'object'
>> ver(2) = ver
ver =
1-by-2 packajoozle.internal.Version

>>

That's from Octave 4.4.1. Same thing happens in Octave 5.1.0 and Octave default 6.0.0 (hg id: 1771bed38482 + patches).