function c = owuitools_text_cell (value, fname, argname)
  %OWUITOOLS_TEXT_CELL  Normalise char / cellstr input for the shims.
  %
  %  Shared by the text shims in this directory. Returns a cell array of
  %  char rows, and refuses anything else by name so the message reads
  %  like the function the caller actually wrote.
  %
  %  The name is prefixed rather than generic because this directory sits
  %  ahead of everything on the path: a file called `text_cell.m` here
  %  would shadow anyone's own helper of that name, in their own script,
  %  with no way for them to see why.

  if (ischar (value))
    if (ndims (value) > 2 || (~isempty (value) && rows (value) > 1))
      error ('%s: %s must be a single row of characters, not a char matrix', fname, argname);
    end
    c = {value};
  elseif (iscellstr (value))
    c = value;
  elseif (iscell (value))
    error ('%s: %s must be text - a char row or a cell array of char rows', fname, argname);
  else
    error ('%s: %s must be text, not %s', fname, argname, class (value));
  end
end