[Octave-bug-tracker] [bug #32060] Accessing OO properties in subfunction of a private class method

[Guillaume]

URL:
  <http://savannah.gnu.org/bugs/?32060>

                 Summary: Accessing OO properties in subfunction of a private
class method
                 Project: GNU Octave
            Submitted by: gyom
            Submitted on: Wed Jan  5 15:50:57 2011
                Category: Interpreter
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: Incorrect Result
                  Status: None
             Assigned to: None
         Originator Name: Guillaume
        Originator Email: 
             Open/Closed: Open
         Discussion Lock: Any
                 Release: dev
        Operating System: GNU/Linux

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Details:

Accessing fields of an object should be done directly from within a method
(ie not calling subsref/subsasgn): while this is the case for a public class
method and for a private class method (see:
https://savannah.gnu.org/bugs/?30909), it is not for a subfunction of a
private class method.

This can be reproduced with the following code:

==================== @testclass/testclass.m ====================
function obj = testclass(varargin)
obj = struct('public',1, 'private',0);
obj = class(obj,'testclass');

==================== @testclass/subsref.m ====================
function dat = subsref(obj,subs)
switch subs.type
    case '.'
        switch subs.subs
            case 'public'
                %dat = obj.param;
                dat = param(obj);
            otherwise
                error('err');
        end
    otherwise
        error('err');
end

==================== @testclass/private/param.m ====================
function dat = param(obj)
%dat = obj.public; % direct access => works
dat = param2(obj); % => subfunction calls subsref => crash

function dat = param2(obj)
dat = obj.public; % calls subsref...

========================================
octave> a = testclass;
octave> a.public

results in an infinite loop param<->subsref in Octave, while this works as
expected in MATLAB.




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