Object based octave instead of Object Oriented Octave...

[James Moliere]

Hello,
I'm trying to learn Octave's new 'Object Oriented Programming'.  I must 
say, I didn't see anywhere in the documentation the concepts of 
inheritance so I recommend that the phrase 'Object Based Programming' be 
used.  Please correct me if I'm wrong.

I also played with a counter class that simply increments when the inc() 
method is called.

octave:1> a=counter(1)
octave:2> b=counter(5)
octave:3> c=counter(2, a)
octave:4> c=inc(c)

with the error
error: class has no member `other'
error: evaluating argument list element number 1
error: evaluating argument list element number 1
error: called from:
error:   /home/jmoliere/octave/@counter/inc.m at line 8, column 8
error:   /home/jmoliere/octave/@counter/inc.m at line 8, column 8

How do I formerly create class members? ...I couldn't find the phrase 
'class member' in the Octave documentation version 3.1.52+.

Thanks!
James Moliere

#this is bad code below but it's just for learning the new features in 
Octave.
@counter/counter.m
------------------------------------------------------------
function cntr = counter(a, other)
   if (nargin == 0)
       cntr.counter = 0;
       cntr.other = [];
       cntr = class (cntr, "counter");
      
   elseif (nargin == 1)
       if (strcmp (class(a), "counter"))
           cntr = a;
           cntr.other = [];
       elseif (isvector (a) && isreal(a))
           cntr.counter = a(1);
           cntr = class(cntr, "counter");
       else
           error("counter: expected another counter or a starting value");
       endif
   elseif (nargin == 2)
       if (strcmp (class(a), "counter"))
           cntr = a;
           cntr.other = other;
       elseif (isvector (a) && isreal(a))
           cntr.counter = a(1);
           cntr.other = other;
           cntr = class(cntr, "counter");
       else
           error("counter: expected another counter or a starting value");
       endif
   endif   
endfunction
-------------------------------------------------------

file: @counter/inc.m
--------------------------------------------------------
# throw away code just to try to understand the new features in Octave.
function c = inc(a)
   a.counter = a.counter+1;
   disp(a.counter);
   #a.other.counter = a.other.counter+1;
   #disp(a.other.counter);
   if (strcmp(class(a.other), "counter"))
       a.other=inc(a.other);
   endif
   c = a;   
endfunction

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