ENHL New utility function getfielddefault

src/private/getfielddefault.m

+% This file is a part of the CaosDB Project.
+%
+% Copyright (C) 2021 IndiScale GmbH <info@indiscale.com>
+% Copyright (C) 2021 Daniel Hornung <d.hornung@indiscale.com>
+%
+% This program is free software: you can redistribute it and/or modify
+% it under the terms of the GNU Affero General Public License as
+% published by the Free Software Foundation, either version 3 of the
+% License, or (at your option) any later version.
+%
+% This program is distributed in the hope that it will be useful,
+% but WITHOUT ANY WARRANTY; without even the implied warranty of
+% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+% GNU Affero General Public License for more details.
+%
+% You should have received a copy of the GNU Affero General Public License
+% along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+%% getfield(...) if the field exists, else default.
+%
+% Additional index arguments are used in both cases.
+function result = getfielddefault(str, field, default, varargin)
+  if (isfield(str, field))
+    result = getfield(str, field, varargin);
+  else
+    result = default(varargin{:});
+  end
+end