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## distribution or <https://octave.org/copyright/>.
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## -*- texinfo -*-
## @deftypefn  {} {} helpdlg ()
## @deftypefnx {} {} helpdlg (@var{msg})
## @deftypefnx {} {} helpdlg (@var{msg}, @var{title})
## @deftypefnx {} {@var{h} =} helpdlg (@dots{})
## Display a help dialog box with help message @var{msg} and caption
## @var{title}.
##
## The default help message is @qcode{"This is the default help string.@:"}
## and the default caption is @qcode{"Help Dialog"}.
##
## The help message may have multiple lines separated by newline characters
## ("\n"), or it may be a cellstr array with one element for each line.
##
## The return value @var{h} is a handle to the figure object used for
## building the dialog.
##
## Examples:
##
## @example
## @group
## helpdlg ("Some helpful text for the user.");
## helpdlg ("Some helpful text\nwith two lines.");
## helpdlg (@{"Some helpful text", "with two lines."@});
## helpdlg ("Some helpful text for the user.", "Fancy caption");
## @end group
## @end example
##
## @seealso{errordlg, warndlg, msgbox, inputdlg, listdlg, questdlg}
## @end deftypefn

function h = helpdlg (varargin)

  msg = "This is the default help.";
  tit = "Help Dialog";
  opt = "non-modal";

  nargs = numel (varargin);

  if (nargs > 2)
    print_usage ();
  elseif (nargs == 1)
    msg = varargin{1};
  elseif (nargs == 2)
    msg = varargin{1};
    tit = varargin{2};
  endif

  htmp = msgbox (msg, tit, "help", opt);

  if (nargout)
    h = htmp;
  endif

endfunction

## No BIST tests.  This function just dispatches to msgbox().
%!assert (1)
