update packages

[CreaPhase.git] / octave_packages / m / miscellaneous / isappdata.m

diff --git a/octave_packages/m/miscellaneous/isappdata.m b/octave_packages/m/miscellaneous/isappdata.m
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+## Copyright (C) 2010-2012 Ben Abbott
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 2 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with Octave; see the file COPYING.  If not, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {@var{V} =} isappdata (@var{h}, @var{name})
+## Return true if the named application data, @var{name}, exists for the
+## object with handle @var{h}.
+## @seealso{getappdata, setappdata, rmappdata}
+## @end deftypefn
+
+## Author: Ben Abbott <bpabbott@mac.com>
+## Created: 2010-07-15
+
+function res = isappdata (h, name)
+
+  if (! (all (ishandle (h)) && ischar (name)))
+    error ("isappdata: invalid input");
+  endif
+
+  for nh = 1:numel(h)
+    data = get (h(nh));
+    if (isfield (data, "__appdata__") && isfield (data.__appdata__, name))
+      res(nh) = true;
+    else
+      res(nh) = false;
+    endif
+  endfor
+
+endfunction
+
+%!test
+%! setappdata (0, "hello", "world")
+%! assert (isappdata (0, "hello"), true)
+%!assert (isappdata (0, "foobar"), false)
+