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## Copyright (C) 1998-2022 The Octave Project Developers
##
## See the file COPYRIGHT.md in the top-level directory of this
## distribution or <https://octave.org/copyright/>.
##
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## -*- texinfo -*-
## @deftypefn  {} {[@var{r1}, @var{r2}, @dots{}, @var{rn}] =} deal (@var{a})
## @deftypefnx {} {[@var{r1}, @var{r2}, @dots{}, @var{rn}] =} deal (@var{a1}, @var{a2}, @dots{}, @var{an})
##
## Copy the input parameters into the corresponding output parameters.
##
## If only a single input parameter is supplied, its value is copied to each
## of the outputs.
##
## For example,
##
## @example
## [a, b, c] = deal (x, y, z);
## @end example
##
## @noindent
## is equivalent to
##
## @example
## @group
## a = x;
## b = y;
## c = z;
## @end group
## @end example
##
## @noindent
## and
##
## @example
## [a, b, c] = deal (x);
## @end example
##
## @noindent
## is equivalent to
##
## @example
## a = b = c = x;
## @end example
##
## Programming Note: @code{deal} is often used with comma separated lists
## derived from cell arrays or structures.  This is unnecessary as the
## interpreter can perform the same action without the overhead of a function
## call.  For example:
##
## @example
## @group
## c = @{[1 2], "Three", 4@};
## [x, y, z] = c@{:@}
## @result{}
##    x =
##
##       1   2
##
##    y = Three
##    z =  4
## @end group
## @end example
## @seealso{cell2struct, struct2cell, repmat}
## @end deftypefn

function varargout = deal (varargin)

  if (nargin == 0)
    print_usage ();
  elseif (nargin == 1 || nargin == nargout)
    varargout(1:nargout) = varargin;
  else
    error ("deal: nargin > 1 and nargin != nargout");
  endif

endfunction


%!test
%! [a,b] = deal (1,2);
%! assert (a, 1);
%! assert (b, 2);
%!test
%! [a,b] = deal (1);
%! assert (a, 1);
%! assert (b, 1);

## Test input validation
%!error <Invalid call> deal ()
%!error <nargin . 1 and nargin != nargout> y = deal (1, 2)