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##
## Copyright (C) 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{mem_fcn_handle} =} __memoize__ (@var{fcn_handle})
## @deftypefnx {} {} __memoize__ ()
## Internal function used by @code{memoize}.
##
## @seealso{clearAllMemoizedCaches, memoize}
## @end deftypefn

function mem_fcn_handle = __memoize__ (fcn_handle)
  persistent cached_mem_fcn_handle;

  if (nargin)

    for i = 1:numel (cached_mem_fcn_handle)
      if (isequal (cached_mem_fcn_handle{i}.Function, fcn_handle))
        mem_fcn_handle = cached_mem_fcn_handle{i};
        return;
      endif
    endfor

    mem_fcn_handle = matlab.lang.MemoizedFunction (fcn_handle);
    cached_mem_fcn_handle{end+1} = mem_fcn_handle;

  else

    for i = 1:numel (cached_mem_fcn_handle)
      clearCache (cached_mem_fcn_handle{i});
    endfor

  endif

endfunction