2 Copyright (C) 2015 Carl Hetherington <cth@carlh.net>
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 #include "raw_convert.h"
21 #include <boost/filesystem.hpp>
22 #include <boost/optional.hpp>
25 class ImageFilenameSorter
28 bool operator() (boost::filesystem::path a, boost::filesystem::path b)
30 boost::optional<int> na = extract_number (a);
31 boost::optional<int> nb = extract_number (b);
33 return a.string() < b.string();
36 return na.get() < nb.get();
40 boost::optional<int> extract_number (boost::filesystem::path p)
45 for (size_t i = 0; i < p.string().size(); ++i) {
46 if (isdigit (p.string()[i])) {
47 number += p.string()[i];
49 if (!number.empty ()) {
55 if (number.empty ()) {
56 return boost::optional<int> ();
59 return raw_convert<int> (number);