[Octave-bug-tracker] [bug #36240] incorrect isargout after using a trailing ~ once

[John Hunt]

URL:
  <http://savannah.gnu.org/bugs/?36240>

                 Summary: incorrect isargout after using a trailing ~ once
                 Project: GNU Octave
            Submitted by: huntj
            Submitted on: Wed 18 Apr 2012 02:53:05 PM GMT
                Category: Interpreter
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: Incorrect Result
                  Status: None
             Assigned to: None
         Originator Name: 
        Originator Email: 
             Open/Closed: Open
         Discussion Lock: Any
                 Release: dev
        Operating System: GNU/Linux

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Details:

The following bug is probably the reason for
bug #36221
which is thus not limited to unique.


the try_isargout.m function attached does not work after 
being called with a trailing ~ as in
[x, ~] = try_isargout()


octave:1> [x, y] = try_isargout()
warning: nbh: 0
ans =

   1   1

x =  4
y =  5
octave:2> [x] = try_isargout()
warning: nbh: 0
ans =

   1   0

x =  4
octave:3> [x, y] = try_isargout()
warning: nbh: 0
ans =

   1   1

x =  4
y =  5
octave:4> [x, ~] = try_isargout()
warning: nbh: 1
ans =

   1   0

x =  4
octave:5> [x, y] = try_isargout()
warning: nbh: 0
ans =

   1   0

x =  4
y = [](0x0)



it seems that p->is_black_hole() returns wrong results,
since nbh is wrong. This sis shown by the warnings I added
line 612 of src/ov-usr-fcn.cc :


 for (std::list<octave_lvalue>::const_iterator p = lvalue_list->begin ();
           p != lvalue_list->end (); p++)
        nbh += p->is_black_hole ();
          
          warning("nbh: %d", nbh);


the behaviour is the same in 3.6.1 and in
the latest hg pull




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File Attachments:


-------------------------------------------------------
Date: Wed 18 Apr 2012 02:53:05 PM GMT  Name: try_isargout.m  Size: 156B   By:
huntj

<http://savannah.gnu.org/bugs/download.php?file_id=25682>

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