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3## Copyright (C) 2012-2021 The Octave Project Developers
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25
26## -*- texinfo -*-
27## @deftypefn  {} {@var{data} =} guidata (@var{h})
28## @deftypefnx {} {} guidata (@var{h}, @var{data})
29## Query or set user-custom GUI data.
30##
31## The GUI data is stored in the figure handle @var{h}.  If @var{h} is not a
32## figure handle then it's parent figure will be used for storage.
33##
34## @var{data} must be a single object which means it is usually preferable
35## for it to be a data container such as a cell array or struct so that
36## additional data items can be added easily.
37##
38## @seealso{getappdata, setappdata, get, set, getpref, setpref}
39## @end deftypefn
40
41function dataout = guidata (h, data)
42
43  if (nargin < 1 || nargin > 2)
44    print_usage ();
45  endif
46
47  if (! ishghandle (h))
48    error ("guidata: H must be a valid object handle");
49  endif
50  h = ancestor (h, "figure");
51  if (isempty (h))
52    error ("guidata: no ancestor figure of H found");
53  endif
54
55  if (nargin == 1)
56    dataout = get (h, "__guidata__");
57  else
58    set (h, "__guidata__", data);
59    if (nargout == 1)
60      dataout = data;
61    endif
62  endif
63
64endfunction
65
66
67## Test input validation
68%!error guidata ()
69%!error guidata (1,2,3)
70%!error <H must be a valid object handle> guidata ({1})
71%!error <no ancestor figure of H found> guidata (0)
72