Matlab and GNU Octave are constantly adding new functionality. However, legacy versions remain in use for years. One in general may not be able to overload a Matlab function in Octave because of how Octave provides many functions as files, and cannot distinguish them from user files.

The “overloading” we do here is to provide a similarly but distinctively named function that seamlessly uses the new syntax when available, with a simple fallback. In this isfile example the fallback only works for single files.

Create a file “is_file.m” containing:

function ret = is_file(path)

if exist('isfile', 'builtin') == 5 || exist('isfile', 'file') == 2
  ret = isfile(path);
else
  ret = exist(path, 'file') == 2;
end

end % function